Encyclopedia of Japanese Minerals (Go to Intro Page)
by Alfredo Petrov
Minerals Starting with "A"
ABRAMOVITE (IMA 2006-016) (aburamov-koh)
Northern Territory: Type locality for this new member of the cylindrite group, Pb2 Sn In Bi S7, is a high-temperature fumarole on Kamui-dake, where it forms minute metallic aggregates less than 1mm size.
ABSWURMBACHITE (abusuburumubahha-koh)
Ehime: With strontian hollandite and tweddillite in a nodule in quartz schist (metachert) in the Saruta-gawa area. Much of this material is actually braunite, but some contains enough copper to be classified as abswurmbachite - 0.30-0.53 apfu Cu (Masaki Enami and Yasuyuki Banno, 2001). (M. Enami and Y. Banno (2000) Ganko-Gakkai Koen-Yoshi, 26.) (at or near Sazare cupriferous pyrites mine??)
ABUKUMALITE (abukuma-seki)
(Considered by some authors to be the same species as BRITHOLITE-(Y) (qv), but it has a different space group (Satoshi Matsubara, 2002 & 2006).)
ACTINOLITE (toh-ryoku-senseki; ryoku-senseki; nephrite jade = nangyoku; ferroactinolite = tetsu-ryoku-senseki)
(Much of the actinolite listed here, and the nephrite, is more technically Fe-rich tremolite. Needs more analyses, and redefinition of the current illogical tremolite-actinolite boundary. "Ferroactinolite" is listed here under actinolite, although illogically considered by some to be a separate species.)
Ehime: Lustrous green to blackish green, thin lathe-like actinolite xls to 7cm in columnar aggregates at Hodono. Similar material reported from Irazuyama.
Fukuoka: At Yanagigaura, actinolite forms light grey to greenish grey aggregates of fibrous crystals in massive magnetite from a contact iron deposit.
Gifu: Nephrite jade at Kijiya. As grey-green fibrous pseudomorphs after 6cm hedenbergite (qv) crystals at Higashihora. Also here as deep green filiform inclusions in quartz (qv) crystals.
Hokkaido: Nephrite jade at Chisaka.
Iwate: Deep green aggregates of acicular xls at the Kamaishi mine, in drusy vugs in contact metamorphic garnet-magnetite skarn ore, some with calcite and vonsenite. Greyish aggregates of fibrous xls at the Sennin mine, as an alteration of hedenbergite in a contact iron deposit. "Ferroactinolite" comes from the Akagane mine.
Kouchi: Green translucent prismatic blades or fibrous xls up to 5cm, without terminal faces, sometimes curved or bent, occur in talcose parts of a crystalline schist at the Yoshino mine. Also from the Shirataki cupriferous pyrites mine.
Nagano: Nephrite jade at Matsukawa.
Nagasaki: Asbestiform actinolite from the Nomo peninsula (Nomozaki) in Nagasaki city. Also from Ohgushi.
Nara: "Ferroactinolite" (rather illogically considered by some to be a separate species) at the Godaimatsu (or Godai) mine, as pale greenish or greenish grey, papier-mache-like microfibrous masses to 2cm.
Niigata: In the jadeite-bearing albitite rocks of the Ohmi district, associated with prehnite plus either chlorite or zoisite+quartz.
Osaka: "Ferroactinolite" is found at Nose.
Saitama: Prismatic xls associated with granular crystalline magnetite aggregates at Nakatsugawa, in contact iron ore. Also in the Nagatoro district. "Actinolites" from Shiroishi in Higashi-Chichibu-mura, and from the Nakoso and Iritohno and Gozaisho-Takanuki districts, are highly Mg-dominant and so are described here under Tremolite (qv).
Tochigi: "MANGANACTINOLITE" was described in 1938 from the Kaso mine, but later recognized to be a manganoan variety of actinolite although, if the tremolite-ferroactinolite series were to be redefined by cation site dominance, as other minerals are, it would be manganoan tremolite (qv) and is here described as such.
AFWILLITE (afuwiru-seki)
Okayama: First found in Japan at the Mihara mine ((1965) Journal of Science of Hiroshima University, 4, 395-428). A much better studied afwillite is found at Fuka, where it forms colorless or white, vitreous, tabular xls 0.1 to 0.3mm wide or acicular xls to 4mm long, in radial aggregates to 1cm diameter, on tilleyite, and as thin veins to 3mm wide, in fractured spurrite rock in calc-silicate skarn. Associated with calcite, spurrite, jennite or oyelite, in parallel layers from 0.2 to 0.5mm wide. May alter to jennite. Unlike the comparable occurrence at Crestmore, California, afwillite at Fuka contains a little titanium and boron (0.1 and 0.4 wt% Ti and B oxides, respectively). (Kusachi et al. (1989) Mineralogical Journal, 14, 279-292.)
AGARDITE-(Y) (ittoriumu-agahdo-seki)
(N.B. Very few agardite specimens from Japan have been analyzed, so much of what is labelled "agardite-(Y)" may actually be other species. Specimens labelled "agardite-(Ca)" are sometimes agardite-(Y) and sometimes zalesiite.)
Hiroshima: At the Setoda mine on Ikuchi island, agardite-(Y) is very abundant in and around a 3m-wide vein of oxidized pneumatolytic copper ore cutting what has now become a granite quarry. As acicular sprays to 3mm, or scattered single xls, in fissures of a whitish matrix; whitish green and silky in tiny xls, lustrous green and vitreous in larger xls, forming light bluish green, thin crusts to several cm wide; often associated with green crusts of cornwallite. (Some of the "agardite-(Y)" from this area is confirmed, but some is actually zalesiite.) (Aruga & Nakai (1985) Acta Crystallographica, C41, 161-163; Miyawaki et al. (2000) Memoirs of the National Science Museum, 32, 19-38.)
Hyougo: Pale green micro-acicular xls and fine sprays with silky luster, on slate at the Kunisaki mine. (Species not certain.)
Nara: Tiny pale green needles with silky luster form sprays to 3mm across, flattened in slate fissures at the Ryujin mine. Also at the Sansei mine, light yellowish green acicular crystals to 1.5mm form divergent bundles. (Ohori & Kobayashi (1996) Chigaku Kenkyu, 44, 223-232.)
AGUILARITE (ryuu-seren-ginkoh)
Fukuoka: Aguilarite from the Kato Cu-Pb-Zn-Au mine was the first selenide found in Japan (1955). Forms anhedral grains to 0.4mm (mostly only 0.1mm), and as tiny fissure fillings along grain boundaries between older galena, sphalerite, chalcopyrite, pyrite. Slightly brownish grey with a yellowish green tint under ore microscopy (browner than acanthite); polishing hardness lower than galena. Often with microscopic inclusions of gold.
Hokkaido: Steel grey aguilarite, as minute grains invisible to the naked eye, is associated with electrum and black pearceite at the Koryu mine (Sugaki et al. (1984) Ganseki-Kobutsu-Koshogaku Zasshi, 79, 405-423). Also reported from the Sanru mine.
Kagoshima: With electrum, naumannite and pyrargyrite in black "ginguro" bands in young (1 million year old) adularia-quartz veins at the Hishikari mine.
AKAGANEITE (akagane-koh)
Iwate: The Akagane mine is the type locality for this iron oxide-hydroxide-chloride. Occurs as orange to orange-brown or brownish yellow earthy material resembling powdery "limonite". Under the electron microscope, exhibits loose, flattened thin prismatic crystals from 0.02 to 0.8 microns long and about a tenth of that in width. Associated with goethite, melanterite and other Fe sulphates in a weathered outcrop. Formed by oxidation of pyrrhotite in a pyrometasomatic copper-iron ore at the contact between limestone and gabbro in Carboniferous greenstone.
AKHTENSKITE (afutensuku-koh)
Osaka: Blackish massive, with compact, metamorphic Mn silicate ore at the Hirono mine.
ALABANDITE (sen-mangan-koh; arabando-koh)
Aichi: With rhodonite in late Paleozoic or early Mesozoic metasedimentary manganese ores of the Hazu district.
Akita: Brownish black, massive banded aggregates of alabandite, are associated with bright rose-pink drusy rhodochrosite in an epithermal rhodochrosite-quartz vein at the Taisei (Ouishi) mine. Brownish black crystalline crust of alabandite, 10cm thick, forms veins in andesite at Saimyohji; covered with crystallized pink rhodochrosite and, later, by excellent rhombohedral calcite crystals. ((same place??))
Gifu: Minor component, with garnet and pyrophanite, in a lens of metasedimentary rhodochrosite-quartz-pyroxmangite ore hosted in grey meta-chert at the Ajiro mine.
Gumma: In massive pink rhodonite ore at the Mogurazawa mine, associated with various rare Ba-V minerals.
Hokkaido: Rhodochrosite-alabandite-sphalerite-galena ore in rhodochrosite veins in Tertiary volcanosedimentary rocks at the Yakumo manganese-silver mine. A common ore mineral in rhodochrosite veins traversing Miocene propylite at the Inakuraishi mine, where it can occur as twinned crystals.
Iwate: Abundant in metamorphosed folded bedded manganese ore at the Noda-Tamagawa mine.
Mie: Alabandite as mm-size grains is richly disseminated in tephroite at the Yamada mine.
Miyazaki: Brownish alabandite with pinkish grey kanoite at the Shimozuru manganese mine (Gunnar Farber specimens).
Saitama:> As greenish black pseudomorphs after tiny rambergite (qv) crystals from the Hirogawara manganese mine. Also as small masses with pyrite and siegenite, embedded in kellyite.
ALLANITE-(Ce) (katsuren-seki)
Ehime: Black prismatic allanite grains to 5cm long form masses associated with quartz, microcline, fergusonite and REE-rich zircon in granite pegmatite at Mategata. Also at Oyama. Analysis of an "allanite" from the Tateiwa mine pegmatite corresponds to (Ca 0.778, Ce 0.292, Y 0.153, Mn'' 0.134, Th 0.041) apfu (Umegaki, et al, 1957; in DHZ), but all REE were here expressed as "Ce", and more modern analysis is needed. Allanite also occurs in aegirine syenite on Iwagi island, with sugilite.
Fukushima: In the Ishikawa district as massive aggregates of 2cm prismatic xls in granitic pegmatite with quartz and microcline. One extraordinary prismatic crystal from Magaki in this district is almost 14cm long, with a resinous light brown color, embedded in white pegmatite matrix. In pegmatite at Hayamadake, with fergusonite, thorogummite and a Y-P-rich zircon. Also in Y-rich rare-earth pegmatite at Suishouyama, with yttrialite, thorogummite and britholite-(Y); (NB: allanite-(Y) also occurs here). An unusually Be-rich "beryllium allanite" with 2.49 wt% BeO was described from feldspar pegmatite at Iisaka (Suishouyama?), but all REE were expressed as "Ce", and more modern analysis is needed: (Ce 0.816, Ca 0.812, Mn'' 0.160, Th 0.006) (Be 0.553, Zr 0.026... ) apfu (Iimori, 1939; in DHZ). In feldspar at Uzumine. Also at Fusamata, and on Kuchibutoyama, and at Shiraiwa. Analyses (REE not separated) are given by Hasegawa (Hasegawa 1958; in DHZ) for the localities Tomita-mura and Takano-mura (probably overlap with some previously listed localities???) and for Magaki.
Hiroshima: With other REE minerals in quartz-feldspar pegmatites in granite in Senogawa-machi.
Ibaragi: Allanite-(Ce) in granite pegmatite at Yamanoo is also rich in neodymium and unusually high in gadolinium (Ce>Nd>Gd). Also at Shimodainou.
Ishikawa: Resinous black prismatic crystals and tabular masses found with biotite and magnetite in pegmatite dikes in gneissic granite and diorite along the beach near "Nagatejima" (= Nagatezaki?) on the Noto peninsula were described as the new species "NAGATELITE" in 1931. Crystals are typically 6 to 7mm long, 2 to 3mm wide, monoclinic, exhibiting faces a(100), c(001), r(101) and l(201), or as platy aggregates 5mm across, rarely up to 15mm. Analysis gave (as wt% of oxides) Si 25.2, P 6.48, Ti 0.57, Al 14.3, Fe''' 2.40, Ce 14.58, La etc. 7.84, Y etc. 4.51, Th 0.88, Fe'' 7.89, Mn'' 1.12, Ca 10.4, Mg 1.04, water 2.35, corresponding to the formula (Ca 1.061, Ce 0.508, La 0.276, Y 0.229, Mn'' 0.090, Th 0.019) (Fe'' 0.628, Mg 0.148, Ti 0.041) (Al 1.558, Fe''' 0.172) (Si 2.400, P 0.552, Al 0.048) (OH) 1.492, which appears to be a phosphate-rich variety of allanite-(Ce). More modern REE separation is needed. (D 3.91; H 5.5; uneven fracture; streak pale brown; RI 1.750 - 1.765; pleochroic brownish yellow, reddish brown and pale brown.)
Kyoto: In a roadcut on the eastern slopes of Daimonjiyama, the first allanite locality in Japan, as black or brownish black, euhedral prismatic xls about 8x1.5x1mm, as an accessory in weathered biotite granite and grus. Analysis corresponds to (Ca 1.113, La 0.366, Ce 0.344, Mn'' 0.047, Y 0.032, Th 0.027) (Fe'' 0.728, Mg 0.120, Ti 0.078, Sn 0.015) (Al 1.833, Fe''' 0.298) (Si 2.885, Al 0.115) (OH) 1.002, but more modern analysis is needed to better separate the REE (Ueda, 1955; in DHZ). Also at Shuugakuin, and in rare-earth-bearing altered microcline pegmatite at Shiraishi.
Mie: At the Naegi mine, as glassy black, long prismatic crystals in brown-stained pegmatite feldspar.
Osaka: At the Sakaguchi mine, a granitic pegmatite once mined for feldspar, allanite forms pitchy brownish black, anhedral masses to 15cm in friable coarse-granular pinkish matrix.
ALLANITE-(La) (rantan-katsuren-seki)
Fukushima: Analysis of a "manganoan allanite" from granite pegmatite at Shiozawa might correspond to Mn-rich allanite-(La), but more modern analysis is needed to better separate the REE: (Mn'' 0.537, Ca 0.510, La 0.416, Ce 0.310, Y 0.154, Th 0.090) apfu (Hasegawa, 1958; in DHZ).
Miyagi: Analysis of a chemically unusual "allanite" from pegmatite at Ohari might correspond to Mn-rich allanite-(La), but more modern analyses are needed to confirm this and to better separate the REE: (La 0.528, Mn'' 0.498, Ca 0.445, Ce 0.265, Y 0.096, Th 0.037) apfu (Hasegawa, 1957; in DHZ).
ALLEGHANYITE (areganii-seki)
(Some alleghanyite from japanese metamorphosed Mn ores may have previously been misidentified as "tephroite". Conversely, some "alleghanyite" reported before the 1960s may be sonolite.)
Gumma: As mixtures with rhodochrosite around eyes of wiserite and jacobsite at the Kurokawa mine. Together with hausmannite, jacobsite and rhodochrosite, forms the dark brown ore bands in bedded chert at the Yamabishi mine.
Nagano: As a major component of high-grade, banded folded manganese ore in Permian metamorphosed chert at the Hamayokokawa mine. The alleghanyite is dark reddish brown, associated with major hausmannite and lesser feitknechtite, manganosite, jacobsite and rhodochrosite. Also as rhodochrosite-alleghanyite ore, with lesser pyrochroite and manganosite. Also with pale pink rhodonite and medium brown to light brownish grey tephroite at contact with surrounding lower-grade ore.
Shiga: Once considered a major ore mineral at the Ioi mine, intimately associated with hausmannite in alleghanyite-carbonate-hausmannite ore, sometimes cut by veinlets of bementite and/or barite, but much of this "alleghanyite" may be really sonolite. Several "veins" of this metamorphosed Mn ore are emplaced along bedding faults in Paleozoic chert about 3km west of outcrops of granitic batholith. The alleghanyite displays lamellar twinning.
ALLOCLASITE (arokurehsu-koh)
Nara: The Dohgatani mine was the first reported locality in Japan for alloclasite. (Kingstone (1971) Canadian Mineralogist, 10, 838-846.)
Wakayama: At least one of the reported "glaucodot" specimens from the Sanyo mine turned out to be entirely alloclasite (XRD by Czech Geological Survey, 2001). (Ohnishi et al. (2004) Kobutsu-Gakkai Koen-Yoshi, 134.)
ALLOPHANE (arofen)
Kumamoto: Allophane occurs abundantly with imogolite as a constituent of soils derived from decomposing pumice in the Hitoyoshi valley.
Kyoto: At the Kasatori mine, in fissures in a kuroko-type barite vein, allophane occured as wide crusts of beautiful, bright pearly lustered, white botryoids up to almost 2cm across. Known as yama-shinju ("mountain pearls"), these classic specimens are now unobtainable.
Miyazaki: Light yellow, botryoidal, in the Tomitaka pyrite mine.
Nagano: In pumice beds as a weathering product of volcanic ash from Ontake volcano, and mixed with halloysite in overlying loamy soils.
Shizuoka: Near the peak of Fuji-san, allophane occurs rarely as pale blue glassy grains to 1mm filling small amygdules, easily mistaken for chrysocolla. These are unstable, shrinking and whitening on dehydration. In ore veins at the Kawazu mine.
ALMANDINE (tetsuban-zakuro-ishi)
Aichi: Purplish brown crystals to 1cm, with quartz and microcline in pegmatite in biotite schist on Mt. Sangane. Dark red garnet in gneiss from Tomiyama (Wada 1904 - old locality; no analysis; almandite ID needs confirmation).
Fukushima: In the Ishikawa district, almandine crystals are found in several granitic pegmatites. Deep brown to brown-black opaque trisoctahedra embedded in feldspar can reach 15cm(!) diameter (Geological Survey, 1970), but are normally only 2cm. In quartz, the crystals are transparent red and only reach 4mm (commonly no more than 1mm). One analysis of Ishikawa garnet gave a molecular composition of roughly 49% almandine, 41% spessartine, 6% grossular, and 5% pyrope. (Spessartine-dominant garnets also occur here.) Black almandines in coarse microcline pegmatite at Suishouyama are slightly yttrian and manganoan, and these can be partially replaced by chalky white yttrian fluorite, or by tengerite. At Kanougami, in non-schistose rocks of the Abukuma metamorphic belt, with staurolite, sillimanite, corundum, hercynite and monazite.
Gifu: Raspberry-pink translucent xls and subhedral grains to 1.5mm are richly disseminated through a fine-grained annite matrix in metapelite at the Kawai mine. Also at Yasuoka.
Ibaragi: At Yamanoo as dark reddish brown to translucent brown or sub-transparent brownish red, lustrous, good sharp euhedral trisoctahedral xls (24 faces) to 3cm (average 1cm) diameter, associated with quartz, orthoclase and muscovite in pegmatite in fine-grained biotite granite. Deep red or reddish brown trapezohedral xls are found in fine-grained muscovite matrix on the edge of a graphic granite zone.
Kyoto: An unusual almandite in "graphic granite" texture with quartz from pegmatite in the Koya quarry.
Nagano: (For "almandine" from Wada-tohge, see under "spessartine".)
Nara: Red-brown, usually translucent crystals, sometimes icositetrahedral, in sand derived from decomposed andesite at Anamushi, accompanied by tiny euhedral sapphires and zircons. Also at Nijohsan.
Saga: Lustrous red-brown complex crystals to 9mm reported from Sugiyama.
Toyama: In Ohyama-machi, almandine aggregates are formed of brownish red dodecahedral xls to 12mm, with minor faces bevelling the edges.
ALTAITE (teruru-en-koh)
Iwate: At the Nojiri gold-silver mine, small grains of altaite, tarnished black, occur with pyrite in fractures and intergranular spaces in a mesothermal milky quartz vein.
Kagoshima: At the Kushikino silver-gold mine, with petzite and hessite as a minor constituent of dark sphalerite-chalcopyrite-galena "ginguro" bands to 1cm thick in quartz-calcite veins. (Shiga and Urashima (1983) Sanko-Gakkai Koen-Yoshi, 123.)
Okayama: With hessite and melonite (qv) in skarn at the Mihara mine.
ALUMOHYDROCALCITE (arumohidorokarusaito)
Gumma: Chromian alumohydrocalcite occurs with chromian dawsonite in serpentinite at Tatarazawa.
Hokkaido: Pinkish to white crystalline aggregates on greyish matrix from Yunotaki (Gunnar Farber specimens).
Hyougo: Chromian alumohydrocalcite with 11.2% Cr oxide (higher than in California occurrence) was found at the Akenobe mine.
Mie: Chromian alumohydrocalcite occurs in the crush zone of "black schist" in the Median Tectonic Line, Sana area, associated with nordstrandite and chromian dawsonite. Pale violet or pink alumohydrocalcite is found at Nyu.
Osaka: Associated with dawsonite in Upper Cretaceous marine sediments in the lower part of the Izumi Group, Kishiwada city. (Aikawa et al. (1972) Ganseki-Kobutsu-Koshogaku Zasshi, 67, 370-385.)
Tochigi: Rose-pink to white radiating fibrous spherules of alumohydrocalcite to 1cm at Tatarazawa. (is this a misnomer for the other Fujioka city in Gumma ken????????????????????)
ALUNITE (myohban-seki)
Gumma: Iriyama.
Hiroshima: At Shoukouzan, pink compact-massive alunite is associated with pyrophyllite in a roseki-type deposit formed from altered Cretaceous rhyolite and pyroclastics.
Hokkaido: Pink to reddish (due to hematite inclusions), plumose massive alunite aggregates to 3cm thick, composed of stacked thin platy crystals with silky luster, form veins in Neogene silicified dacitic pyroclastics at Gakkarizawa and Asari Tenguiwa. Other widespread acid alteration halo replacement products here include fine-grained pyrophyllite and topaz.
Hyougo: At the Tochihara mine, thousands of tons of alunite were mined for production of alum and fertilizer. Also at Okamoto.
Kagoshima: Some rhyolite near the peak of Iwo-dake volcano on Satsuma-Ioujima has been leached by acidic fumaroles to a high-silica tridymite-cristobalite-alunite rock, although alunite-bearing rock is less common here than pure silica "keiseki".
Kyoto: White crusts coat fissure surfaces in the decomposed cordierite hornfels at Yunohana, the popular "sakura-ishi" collecting spot.
Shizuoka: Alunite (really mostly natroalunite?) was mined in the Ugusu hot springs area, a replacement deposit of wide horizontal extent, with a silicified upper zone and kaolinized lower zone. Opaque white platy crystals or pseudomorphs to 2.5cm form large crusts.
"AMBER" (kohaku)
(Although not a true mineral, this natural resin is included here because of its geologic environment and its frequent presence in mineral collections.)
Chiba: At Togawa in Choushi city, rounded aggregates and lenticular masses to 9cm of translucent to transparent, reddish brown to deep orange amber with waxy to resinous luster, some including insects, erode out of early Cretaceous (120 million years b.p.) coal-bearing sediments in beach cliffs, which makes this among the oldest ambers in the world. (Other references give the age as Tertiary.)
Fukuoka: Mesozoic amber associated with a coal mine near Kitakyushu city.
Gifu: 33,000 year-old "Pleistocene" copal comes from Mizunami. With properties between those of copal and amber, it has been considered either the worldÕs "oldest copal" or "youngest amber", either way an arbitrary distinction. For a brief period was found abundantly in a roadcut during highway construction.
Hokkaido: Tertiary amber is found in western Hokkaido, associated with coal.
Ibaragi: Yellowish brown to dark reddish brown masses about 3cm in size are found in coal-bearing sediments at Hanakawa.
Iwate: In various localities in Kuji city, for example at Goishi, 85-million-year-old (late Cretaceous) water-transported amber was mined from marine sediments of the Kunitan and Taneichi Formations, sometimes associated with mososaur teeth and ammonites. (From low crumbly bluffs behind tetrapod-lined beach.) Exhibits a wide range of colors, including transparent yellow to orange, translucent cream to caramel to light brown. Insects and a partial bird feather have been found in it. This was the oldest amber used in carvings (amber of this age normally being too brittle), and several tons annually were mined and exported to China for this purpose. Japanese emperor Toyoshi-karu-no-oji presented Chinese Tang-dynasty emperor Kao Tsung a peck-sized (9 liters) Kuji amber around 650 A.D. An opaque yellowish orange 22Kg lump was found in 1927, and a similarly colored 16Kg piece is preserved in the National Science Museum, Tokyo. Other specimens can be seen at the Kuji Amber Museum, and at the American Mus. of Nat. Hist. (entomology coll.), New York. The larger pieces are among the largest lumps of amber in the world. Small nodules, mostly opaque whitish, can still be collected on the coast after storms, and some locals scrape shavings off of these for mixing with incense. Nearby coal strata yield the resin variety "retinite".
AMMONIOLEUCITE (anmoniumu-hakuryuu-seki)
Gumma: Opaque vitreous white, sharp pseudomorphs of ammonioleucite after analcime crystals to 4mm formed crusts at the type locality, Tatarazawa in the Sanbagawa metamorphic belt, with leucite. (Considerable potassium replaces ammonium.) Sometimes also as powdery replacements and sometimes as only partial replacement of the outer shell of the trapezohedral analcime xls, in dolomite-analcite veinlets, fractures and cavities to several cm wide in a greenish hydrothermally dolomitized rock (originally metamorphosed sandstone) from which all the original silicate minerals have disappeared. This occurrence has now been completely worked out. Analysis gave (as wt% oxides) Si 61.05, Al 21.86, (NH4) 8.01, K 4.11, Na 0.712, Ca 0.449, Mg 0.184, Fe'' 0.129, water 2.12, C 2.05.
AMORPHOUS SULFUR
Hokkaido: Liquid sulfur in enormous quantities existed for several months in 1936 when a sulfur lava flow erupted from Iuozan. (There is evidence for other sulfur lava flows in prehistoric times in other parts of Japan; Qv under Akita-ken and Iwate-ken in the "SULFUR" section.) Liquid sulfur exists permanently as a pool at around 40 meters depth under Ohyu-numa crater lake. In plastic masses called "rubber-sulphur" by Wada in 1916 (and "sulfurite" by other authors) from the Kobui sulfur mine (slowly crystallizes to alpha-sulfur with age).
ANATASE (eisui-seki)
Gifu: Biterminated prismatic crystals to 1mm on K-feldspar, and as inclusions in fluorite, in granite quarries in Hirukawa village (and perhaps also elsewhere in the Naegi pegmatite district?). Sharp but very tiny trident-like trillings to 0.1mm in Fukuoka (at the Fukuoka Be mine??).
Nagano: In pale blue-green pyrophyllite from the Honami mine. Crystals to 1mm with brookite and quartz crystals in limonite-filled vugs at Ikura.
Nagasaki: Red-brown crystals in silicified rock at the Nariai lead-zinc mine were analyzed as (Ti 3.944, Al 0.009, Fe''' 0.004) O 8, with 0.09 wt% silica, 0.47% MgO (Minato & Okamoto, 1957; in DHZ).
Osaka: As pale tan sand at Tawara.
Shiga: Deep blue, steeply bipyramidal anatase crystals to 3mm size were found at Ozekigoe perched on partly clear quartz crystals over 1cm long.
Yamanashi: Black anatase crystals from 0.3 to 4.0mm (mostly at the very low end of that range) form inclusions, together with mica, in colorless quartz crystals at Takemori, and nearby at Hirasawa. Also with quartz at the Otome mine.
ANDALUSITE (kohchuu-seki; chiastolite = kuushoh-seki)
Fukuoka: At Daisen, the boundaries of massive quartz-orthoclase-muscovite aggregates in a granite pegmatite produce reddish brown radial aggregates of prismatic andalusite xls to 8cm. (Paragenesis similar to those of Fukushima-ken.)
Fukushima: At various localities around the Ishikawa district, mostly in the same unusual paragenesis: The largest crystals, up to 40cm(!), deep red, sometimes longitudinally heavily striated, rimmed by muscovite, at the boundary of quartz cores of pegmatites at Kita-Sugama (Kitasugawa). Sometimes with deep blue included grains of corundum. At Minami-Sugama, weathered out of pegmatite, or still embedded in white quartz, as well-defined elongated prismatic crystals to 8 cm long, red in the core, but with outer zone more or less decomposed to mica, giving uneven dull faces; sometimes completely pseudomorphed by mica, losing the red color. An analysis on partly decomposed material showed about 9% of the alumina replaced by other oxides and water (K 3.95, Na 2.51, Fe''' 1.15, Ca 0.58, Mg 0.08 as wt% oxides). At Kosugama as pinkish brown columnar xls to 4cm, more or less decomposed and surficially replaced by muscovite, in granitic pegmatite. Similarly, weathered out of pegmatite at Mujinamori, and also in a vein here with tourmaline and garnet. At Teshirogi, pale reddish columnar xls to 10cm long, associated with granular corundum, form aggregates in a granitic pegmatite composed of orthoclase, quartz and muscovite. Also at Kabutsu.
Hokkaido: At Chirorogawa. The Mn-rich variety "viridine" occurs at Chiei.
Ibaragi: In pegmatite and hornfels at Hanazonoyama, as violet-pink, rough columnar diverging xls to 13cm long, with ilmenite. Reported from Fudouzaka.
Iwate: "Chiastolite" at Usuginu, with typical cross-section of square outline with black carbonaceous cross, crystals to 9mm long, in black slate at amphibole granite contact. Also at Iwaizumi, and at Sumita.
Kyoto: Abundant at several localities in Wazuka-cho: Pinkish or light red, square prismatic "chiastolite" ("kuushoh-seki") crystals to 5cm long and 5mm wide richly embedded in black andalusite-mica hornfels at the Koya road metal quarry. Grey-brown simple prismatic crystals to 4.5cm long and 4mm wide are abundantly embedded in hornfels in the steep north bank of the Kizu river. Square prismatic andalusite crystals reach 2x2x20mm at Shimojima in hornfels in a granite contact aureole. Unaltered portions are reddish translucent, altered exteriors opaque white. Andalusite-bearing hornfels and schists are washed as pebbles down the Kizu river and can be found downstream on gravel bars in Kamo-cho too. Also in Kasagi and in Yamashiro; and also on Daimonjiyama in Kyoto city.
Mie: Silvery white columnar crystals to 4cm at Okugano. Also in Owase.
Miyagi: Unaltered, transparent orange, prismatic crystals in contact-metamorphosed slate in a granite contact zone at Hamada.
Nagano: Reddish prismatic crystals, with typical carbonaceous "chiastolitic" cross-section, at Miyata. Also in Minowa and in Takatoh towns (probably one of these duplicates Miyata entry). Some large crystals from pegmatite wall rock in biotite granite (similar to the Fukushima-ken ones).
Nara: As mm-size grains disseminated in an unusual granite porphyry along the Misen river in Tenkawa-mura, associated with ominellite (qv), sekaninaite, dumortierite and topaz.
Rikuzen (Miyagi or Iwate?): At Niiyamahama (similar to those from Hamada, Miyagi).
Tochigi: Square crystals with pleochroic centers (red along the c-axis, green perpendicular to this) and colorless outer zone, chiastolitic diagonal fissures, at Matsuda and Nagusa in clay slate near contact with amphibole granite. Also in metasedimentary rock at Itaga.
Toyama: In cordierite veins traversing polymetamorphosed pelite in Unazuki.
ANDERSONITE (andahson-seki)
Gifu: With zippeite in the relatively recent Tsukiyoshi ore
deposit, Tohnoh mine, in sedimentary rock.
ANDORITE (andoru-koh) (see also NAKASEITE)
Akita: At the Innai mine, in quartz veins containing black bands rich in electrum and a variety of silver sulfosalts.
Hyougo: (Some researchers consider the nakaseite (qv) from the Nakase mine to be a copper-bearing variety of andorite.)
ANDRADITE (kaitetsu-zakuro-ishi)
Fukui: Andradite and manganoan hedenbergite are the major components of some skarn zones hosting Zn-Pb-Ag ores in the Nakayama orebody at the Nakatatsu mine. Zoned crystals, yellowish green to yelowish brown, form oval aggregates 1 to 2 cm across. One wet chemical analysis gave (oxide wt%) Si 35.81, Fe''' 29.79, Fe'' 0.73, Mn 0.86, Ca 32.87, Na 0.10, P 0.15, water+ 0.24, which corresponds to about 96% andradite molecule.
Fukuoka: Dark brown crystals with magnetite at Yanagigaura, in contact zone between limestone and granite (old locality from Wada 1904 - ID needs confirmation). Dark brown, 1cm crystals embedded in coarse-grained calcite from sulphide-bearing skarn at Sannotake.
Fukushima: Isolated crystals, almost black, from 2 to 3cm, at Takanuki (andradite?). Crystals 3cm or bigger in skarn at Tokura (NB: Grossular (qv) also reported from here; analyses needed). (same place??)
Gifu: Sharp, dark green crystals from Hatasa (1904 Wada locality; no analysis; ID needs confirmation).
Iwate: At the Sennin mine, andradite forms yellowish brown aggregates of granular dodecahedral crystals in a hematite-actinolite skarn in contact metasomatosed iron ore. At the Kamaishi mine, as massive aggregates with epidote and magnetite in skarn in a contact metamorphic iron deposit. Crystals reach over 3cm, but often subhedral, deformed or flattened, vary from brown to green, brown ones larger, sometimes zoned with green exterior and brown interior. Also titanian andradite here, with vesuvianite, tilleyite, calcite and various sulfides (including tochilinite), forming high-temperature skarn in the Shinyama Cu-Fe orebody. "Grandite" occurs in the Shinyama orebody too. (Note: Grossular also occurs here, and the "grandites" need analysis for species determination.) Also at the Akagane mine.
Kyoto: In contact metamorphic rock at Gobbesho near Kyoto city (old locality from Wada 1904; andradite ID needs confirmation?).
Miyazaki: Brownish yellow, perfect dodecahedrons, 2 to 3mm, at Yamaura (Toroku mine area), associated with danburite in skarn. (Both andradite and grossular occur here.) Also as druses of greenish brown crystals from 1 to 7mm in neighboring Hinokage-cho.
Nagano: Well-crystallized andradite occurs in skarn at the Kobushi mine. The andradite here is gold-bearing and was successfully worked commercially for gold 35 years ago. Perfect black opaque crystals about 1 cm across in gneiss at Iijima. Groups of dark green opaque crystals from Kawahage in the Kinpuuzan district. Groups of olive-green crystals from Tokiwa. (The last 3 are all old localities from Wada 1904 (crystallographic data available); no analyses given, so might not be andradite.)
Nara: "Rainbow garnet" crystals in a skarn, parts of which had previously been mined for magnetite, at Kitakado. Loose crystals to 2.5 cm, but most less than 1cm, brown and partly transparent, with iridescent schiller in a layer under the surface of crystal faces, sometimes sold with faces polished flat for better display, and the best lapidary material can sell for $100 to $300 per crystal. Analysis shows that this is almost end-member andradite, with no Al or Ti. Collectors have dug a 3m hole into an essentially pure granular aggregate of andradite, taking out at least a ton of rainbow garnet. Specimens from here often bear "Kohse mine" or "Gyojagaeri-dake" labels; both of which are in the immediate vicinity. Originally discovered by Haruhiko Ooe in 1995, the site didn't become famous among collectors and lapidarists until after an abundant find in 2002, with more uncovered by heavy rains in summer 2004, although local authorities have since prohibited further digging. Also in contact metamorphic rocks at Dorogawa. Blackish brown crystals in sulphide-bearing skarn at the Kuzei mine (misnomer for the Kohse mine??).
Okayama: Deep brown trisoctahedral xls in skarn in contact metasomatosed ore at the Yoshioka copper mine. Also in white skarn with xonotlite, wollastonite and diopside at the Sanpoh quarry. The "schorlomite" (qv) at the Fuka mine is titanian andradite. Bright lemon-yellow andradite also occurs here as rims around black schorlomite.
Okinawa: With hedenbergite and quartz in skarn on Tonaki island, at contact between limestone and volcanics. A small abandoned garnet mine lies at the northern tip of Tonaki island.
Ouita: In contact metasomatized limestone at the Kiura mine, pitch black garnet crystals line drusy vugs in crystalline massive garnet from contact metasomatosed limestone. Smaller reddish brown garnets attached to vesuvianite here. (old references from Wada 1904; IDs need confirmation). With hastingsite in skarn at the Obira mine.
Saitama: Associated with diopside and apatite in contact metasomatosed iron ore at Uzunosawa, Nakatsugawa, in the Chichibu mine. (Grossular also occurs at the Chichibu mine.)
Shiga: Very dark, almost black, lustrous, sharp dodecahedral floater crystals to 3.5cm at Otsukumi.
Shimane: Stannian (!) andradite, with the tin incorporated by coupled substitution of quadrivalent Sn + divalent Fe for trivalent Fe, occurs in massive garnet-wollastonite skarn in the upper and middle parts of the Maruyama Au-Cu-Pb-Zn-W orebody of the Tsumo mine.
Yamaguchi: Yellowish brown to greenish brown, translucent simple dodecahedral "grandite" xls to over 3cm (normally less than 1cm), with well-developed (110) faces, form crystalline masses in contact metasomatosed limestone (skarn) at Kamihogi and Shimohogi. The composition of a greenish brown specimen corresponds to 82.9% andradite molecule, 11.3% grossular, 5.5% pyrope, 0.3% spessartine. Some garnets here exhibit iridescence (only the 3rd locality in the world for iridescent garnet), caused by very thin (ca. 2 micrometers) growth lamellae (with alternating optic orientation) parallel to the faces. Polished sections show zoning with large (110) sectors and small (112) sectors, although no (112) faces are visible on the crystal surface. (Ref: AM 69, 896-901 (1984).) Also in Iwakuni city ((same place??)).
ANGLESITE (ryuusan-en-koh)
Akita: At the Kisamori mine, anglesite forms translucent white, short prisms up to 3cm diameter, with (210), (101) and (001) faces, in cavities in oxidized copper-lead-zinc ore. The nearby Arakawa mine produced translucent dark grey prismatic crystals to 3.5cm, elongated on the c-axis, with rough faces and much internal cracking. Terminated by macrodome and basal faces. Common at the Osarizawa mine in a Pb-Zn-Cu oxide zone with kaolinite, limonite, osarizawaite and other secondary minerals. At the Kosaka mine, sharp crystals of simple habit to 6mm form groups or druses lining vugs in oxidized veins.
Fukui: Colorless transparent crystals to 8mm, of simple habit, at Mizunashi-jiki.
Kagoshima: Deposited fumarolically at temperatures between 400 - 650 C in the crater floor of Iwo-dake on Satsuma-Iwojima.
Nagano: As white translucent, spindle-shaped octahedra with (421) faces, in fractures in oxidized pyrite-galena-sphalerite ore at the Ouhinata mine. Also at the Saku mine.
Okinawa: Presently forming in the "Jade" offshore hydrothermal field in the Izena Cauldron.
Yamagata: As pale brown to grey octahedra showing (421) faces, in oxide zone at the Karatoya copper-lead-zinc mine.
ANHYDRITE (koh-sekkoh)
Akita: Pale violet white anhydrite crystals form aggregates in a gypsum deposit by a kuroko-type orebody in Miocene dacitic tuff at the Hanaoka mine. In kuroko ore at the Fukazawa mine.
Fukushima: As aggregates of pale bluish white, thin prismatic crystals associated with "alabaster" gypsum in a kuroko-type gypsum deposit at the Kanou mine. Also at the Yonaihata (Yonaibata) mine.
Ishikawa: Pale pink, coarsely crystalline masses to several cm, associated with fine-grained white gypsum in kuroko-type ore at the Noto mine. Also at the Wakayama mine.
Miyagi: Columnar crystals to 4cm form parallel aggregates in the Sasaya tunnel. Also at the Miyazaki mine.
ANILITE (ani-koh)
Akita: The type locality for this copper sulfide is the Ani mine, where it occurs intimately associated with djurleite in vuggy quartz in Fe-poor areas of the secondary enrichment zone. (Bornite forms in zones with more Fe.) Anilite forms bluish grey, prismatic platy crystals, exceptionally to 2.3cm, striated parallel to the elongation, resembling chalcocite. It is sectile, with no cleavage. (Black streak; H 3; weakly pleochroic, otherwise optically similar to digenite.) Microprobe analyses show only Cu and S. No pure anilite has been found - all studied crystals have included both anilite and djurleite phases, although the anilite component dominates in some. Grinding at room temp. converts it into a cubic metastable digenite-type phase (so no powder XRD pattern?); and heating to about 70 C converts it into covellite plus high-digenite. Also at the Hanaoka mine.
ANNABERGITE (nikkeru-ka)
Hyougo: Light green earthy crusts and chalky masses to several cm at the Natsume nickel mine, on nickeline and gersdorffite in serpentinite. Also at the Horai mine (sic?? -Bideaux).
ANNITE (tetsu-unmo)
(Some of the unanalyzed material listed under "Biotite" is probably annite, and some of the "Protolithionite" might be lithian annite.)
Fukushima: The "biotite" in muscovite-biotite-microcline-quartz schist at Kaiya seems to be magnesium-rich annite, empirically (K 0.97, Na 0.07, Ca 0.06) (Fe'' 1.17, Mg 0.98, Mn 0.02, Fe''' 0.20, Ti 0.10, Al 1.34) (Si 2.75, Al 0.25) 0 10 (OH) 1.72, with 0.10 wt% P2O5. The "biotite" in sillimanite-bearing pyralspite-biotite-oligoclase-quartz gneiss at Chinokubo also analyzes as magnesium-rich annite, empirically (K 0.94, Na 0.03) (Fe'' 1.17, Mg 0.92, Mn 0.02, Fe''' 0.14, Ti 0.10 Al 1.47) (Si 2.70, Al 0.30) O 10 (OH) 1.87, with 0.05 wt% P2O5. (Both analyses from Miyashiro, 1958; in DHZ.)
Gifu: Greenish brown-black, fine-grained flaky annite masses occur with granular raspberry-pink almandite and dark green-brown to grey-green ferrogedrite in contact metamorphosed pelite at the Kawai mine.
ANORTHITE (kai-chohseki; "bytownite" = akai-chohseki; "labradorite" = sohkai-chohseki) (All references are traditional "anorthite", unless the Na-rich varieties labradorite or bytownite are specified here.)
Chiba: "Labradorite" at Gojukura. "Bytownite" on Mineoka-yama (Mineoka mine?).
Hokkaido: Anorthite can be found as phenocrysts to 5cm in a 2-pyroxene-andesite lava flow at the Kuttara caldera. Crystals to several cm were ejected as mini volcanic bombs in great quantities from Tarumae volcano's April 1909 eruption, partly coated with pale grey pumice; analysis gave (An 91, Ab 09), with minor K (0.07 wt% oxide), Fe''' (0.10 wt% oxide), a trace of Mg, no Ba or Sr. Loose crystals can be collected from the unconsolidated pumiceous andesitic pyroclastics. Simple blocky, translucent creamy white to brownish crystals to 3cm occur as separable phenocrysts in andesitic tuff at Fugoppe (erroneously in some references as "Otaru-shi"); analysis corresponds to (Ca 3.720, Na 0.152, Mg 0.091, K 0.006) (Al 7.835, Fe''' 0.060, Si 8.133) apfu (Takubo, 1941; in DHZ). "Labradorite" at Komagatake. "Bytownite" from Showa-Shinzan volcano gave an analysis corresponding to (Ca 3.524, Na 0.420, K 0.021, Mg 0.014) (Al 7.432, Fe''' 0.121, Ti 0.008, Si 8.448) apfu (Yagi, 1949; in DHZ).
Iwate: "Bytownite" on Yakushiyama.
Kanagawa: As phenocrysts in dark basaltic or andesitic dike rocks at Hakone volcano, especially at Tonosawa hot spring, easily removed from their host rock. Rarely, Hakone anorthites have inclusions of native "brass" and copper. Volcanic ash beds near the coast of the Miura peninsula yield rare colorless gemmy crystals which have been cut as fine gems. "Bytownite" at Yaga.
Kumamoto: "Labradorite" at Matsuo.
Miyagi: White or pale pinkish white loose "bytownite" crystals to 2.5cm at Mitaki.
Saga: "Bytownite" at Nishigatake.
Shizuoka: Clear anorthite crystals occur in an olivine-eucrite block in tuff at Wadaki, analysis corresponding to (Ca 3.892, Na 0.094, Mg 0.017) (Al 7.818, Fe''' 0.081, Si 8.098) apfu (Tsuboi, 1935; in DHZ). Also at Aharada.
Tochigi: Phenocrysts in volcanic rock on Kohshinyama, easily separated from their host rock.
Tokyo: The well-known anorthite crystals ejected as many thousands of little volcanic bombs during the July 1874 eruption of Miyake islandÕs active volcano (Oyama) are now represented in systematic mineral collections the world over. ("1870 eruption" in another reference; uncertain, since they were not reported in the mineralogical literature until 1889, by Y. Kikuchi.) Remarkably close to end-member anorthite: (An 97, Ab 02) to (An 96, Ab 04), with minor MgO (0.20 wt%) (SrO nil). These blocky xls rarely exceed 2.5cm size, although examples up to 2 x 5cm are known, and they are always coated with a dull black to brick red or brown glassy film of lava. The smallest measure around 1cm. They can also protrude from the lava surface but are always coated with the characteristic lava film. Also inside larger volcanic bombs and scoria. Usually transparent colorless to translucent whitish on the inside, but a few (less than 1%) exhibit "sunstone"-like schiller due to very thin parallel films of included native copper and Cu-Zn alloys, typically 1 or 2 such layers per crystal. Such crystals appear colorless or metallic pink viewed perpendicular to the discontinuous copper layers, and transparent colorless or a peculiar light blue in transmitted light parallel to the metal. (One dedicated collector needed 2 weeks to collect 10kg of cutting rough for cabochons, and very little of that was truly gem quality.) Extremely rare, transparent deep red xls have been facetted as gems and are highly valued in Japan. Collecting on Miyake is not possible at present since the entire population has been evacuated due to ongoing eruptions of enormous volumes of sulfur dioxide gas. Very similar "anorthites" come from Iwo island (although most crystals from here are of andesine composition. Anorthite labels reliable?). Short prismatic xls to a few cm are also found in andesitic lava on Oushima island. Also on Hachijou-jima, where the crystals, up to 3cm, are on average larger but more opaque than their Miyake-jima cousins; (An 96, Ab 04) in composition.
Yamagata: As phenocrysts to 2cm at Zaoh volcano, easily extracted from their porous andesite breccia matrix.
ANORTHOCLASE (anorusokurehsu)
Kagoshima: With roedderite in pyroxene andesite lava on Iou island.
Saga: "Anorthoclase sanidine" in riebeckite trachyte on the north coast of Madarajima gave an analysis corresponding to K 2.35, Ca 0.09, Na 1.62, Mg 0.003, Fe''' 0.085, Al 4.30, Si 11.72 apfu (Aoyama, 1941; in DHZ).
Wakayama: Anorthoclase as single crystals, Carlsbad twins and Baveno twins, associated with beta-quartz as phenocrysts in rhyolite at Kusukidani. (See also under Sanidine.)
ANTIMONPEARCEITE (an-piasu-koh)
Niigata: Mikawa mine.
Shizuoka: At the Seikohshi mine, sometimes together with orange-red xanthoconite crystals.
"AQUACREPTITE" (a poorly studied species)
Iwate: Miyomori is the type locality for this inadequately studied species, described by Z. Harada in 1936. (Mg,Fe''',H,Al)4 (OH)8 Si 4 O 10 .nH2O ? Sometimes given as Mg3 Si4 O 10 .5H2O or Mg3 Si4 O 11 .5H2O. Perhaps = Fe-rich saponite? (locality = Miyamori talc mine?). The name is presumably derived from the crackling sound heard when the dry material is wetted, as in the case of the earlier Pennsylvania "aquacreptite", whose relationship (if any) to the Miyamori aquacreptite is not known.
ARAGONITE (arare-ishi)
Akita: Groups of transparent prismatic aragonite xls occur as a secondary mineral in fractures in oxidized portions of a chalcopyrite-quartz vein at the Arakawa mine.
Aomori: Aragonite is being deposited as little layered concave terraces about 10cm across around hot springs on the margins of the Osorezan geothermal field, at spots where carbon dioxide is being released by the hot water.
Chiba: Light lilac-colored prismatic crystals to 4cm long with stellate cross-section due to twinning, translucent with bright luster, at Nagasakibana, in amygdules in Paleocene andesite lava along about a 100m stretch of rocky shoreline subject to pounding waves. Also as white to lilac radial acicular sprays to 2.5cm diameter. Aggregates of transparent acicular xls to 1cm long are found at Katsuyama in fractures in serpentinite.
Ehime: The globular "hailstone" variety (but smaller than the similar ones from Taira, Nagano-ken) sparingly at Ichinokawa.
Fukuoka: Fibrous crusts are being deposited from hot spring waters in pipes and channels at "Kwankaiji". ((=Futsukaichi onsen??????))
Gifu: In the contact metasomatosed lead-zinc deposit at the Kamioka mine, transparent acicular xls form slightly bluish white aggregates as botryoidal crusts and stalactitic masses, as a secondary mineral in fractures. "Kikuseki" or "kiku-ishi" ("chrysanthemum stones") are stellate aragonite aggregates, now paramorphed by calcite, from a hill in the Maruyama valley, in red chert derived from acid tuff, and in "schalstein" greenstone derived from pyroclastics.
Gumma: Fibrous crusts are being deposited by hot spring waters in Ikaho. Crusts of pure white acicular crystals less than 1mm long, coating serpentinite fractures at the Dainara nickel mine.
Hyougo: Massive scaly, milk-white "schaumkalk" aragonite, with pearly luster resembling oyster shell, at Arata. ((ref: Wada 1904 - This is probably the same material described elsewhere as "aphrite" calcite.))
Ibaragi: At the Shiozawa coal mine, white stalactitic and coralloidal "flos ferri" aggregates to 12cm, with radial acicular internal structure, formed as a post-mining product in an abandoned adit. Locally known as "yama-sango" ("mountain coral"). Delicate coralloidal stems, snow-white, at Kanayama ((same place?????)). Similar "yama-sango" comes from the walls of abandoned adits at the Gohdo mine and the Kokuji mine.
Ishikawa: Light violet-pink to purple, transparent prismatic xls to over 2cm form beautiful stellate aggregates almost filling round, celadonite-lined amygdules to 2.5cm diameter at Koiji in Uchiura-machi.
vKanagawa: Porous crusts of banded white to light brown aragonite, fluorescent, are being presently abundantly deposited around hot spring installations in Yugawara.
Kouchi: As loose fossil "fish ear stones" (sakana-no-jiseki) in Muroto city. These range from 4mm to 1cm wide, and come from species like hadaka-iwashi (a type of sardine) and soko-dara (a type of cod).
Kumamoto: Presently being deposited from hot spring waters as fibrous crusts in Aso.
Mie: Clear colorless to white xls in fissures in serpentinite on Sugashima island at the Tsuruta Sekizai CompanyÕs quarry. At Shiraki, yellowish white acicular xls to 1cm form lawn-like crusts.
Nagano: At Taira, aragonite occurs around a hot spring as globules to 4cm named "arare-ishi" after the japanese word for hailstones (which then became the japanese for all aragonite). The balls have a concentric, radial-fibrous structure with a rock fragment nucleus. Larger balls exhibit a dodecahedral shape with rounded edges and slightly depressed pentagonal faces, perhaps caused by uniform balls piling up in their most stable packing. Analyses may show magnesium (to over 4% MgO) or manganese (to over 7% MnO). Also occurs here as pale pink sinter-like crusts. Rounded or irregular-globular, concentric, white "calcareous oolites" as a hot spring deposit at Yumata onsen on the upper Takasegawa river. Some take on a peculiar dodecahedral form with depressed pentagonal faces, to 1cm (sometimes considered to be calcite). (Same place as Taira???) Mammillary incrustations of alternating light brown and dark brown bands occur in fractures in serpentinite at Kashio, sometimes made into beautiful polished slabs. Transparent white, prismatic crystals form drusy veins in serpentinite at Outakigawa. Also at Aoki and at Takaiwa (overlap/duplication of places here????).
Niigata: Sky-blue to pale sea-green superb mammillary crusts and crestate curtains to over 30cm across at the Akatani iron mine, in a contact-metasomatosed hematite deposit. These aragonite growths, perhaps among the world's finest (eg: Fossa Magna Museum specimen) are composed of subparallel needles, sometimes partly covered by younger acicular sprays and paler colored "flos ferri" aggregates.
Shimane: Spheroidal nodules from 5cm to 40cm(!) diameter, composed of radially arranged, transparent pale violet or grey to bluish or colorless, with white translucent edges, short prismatic pseudohexagonal trillings to 7cm across (but commonly no more than 2cm across and 3cm long), with (001), (110), (011) and (010) faces, occur loose in a smectite clay zone derived from decomposed dacitic tuff around a Miocene kuroko-type gypsum deposit at the Matsushiro mine. These aggregates now enjoy "national monument" status and cannot be collected without government permission.
Shizuoka: At Toi, in vugs in propylite with zeolites. Currently being deposited as compact banded crusts of fibrous structure, fluorescent, from hot spring waters overflowing wells and tanks at Yugawara-onsen.
Tochigi: As a hot spring deposit at Kuriyama Yuzawa.
Tottori: Coralloidal knobbly growths to several cm, white inside but with a brown surface skin, hang from the walls and ceiling of a sea cave in volcanic agglomerate at Ryujindou.
Wakayama: Chalky white spherical aragonite nodules to almost 2cm are found in Shirahama-cho. The balls are formed of radially arranged aragonite crystals 1 to 2mm across at the surface.
Yamaguchi: Radial-fibrous hemispheres around 5mm diameter in vugs in basalt from Mutsure.
ARDENNITE (arudennu-seki)
Ehime: Dark beige ardennite is found at Kawaguchi and Kamogawa river in Saijyo city (Irita mine?).
Gumma: In Sanbagawa metamorphic terrain of the Kanto Mts., as at Ohnara in Onishi-machi. Likewise at the Tano (Oniishi, Yashio) nickel-cobalt deposit.
Kagoshima: Reported with "yamatoite" at the Yamato mine.
Kouchi: In banded quartz-piemontite schists (0.5 to 2mm bands) in Sambagawa metamorphic terrain in the Asemi-gawa area. Analysis shows (Mn 3.67, Ca 0.53) (Al 4.47, Mg 1.02, Fe''' 0.20, Cu 0.03, Ti 0.01) (As 0.80, V 0.09) Si 5.25...., so it would seem that As is partially replaced by Si. This was the first find of ardennite in crystalline schist (Enami, M., 1986). Orange to yellow-brown, crystalline aggregates to 7mm, or veinlets to 2mm wide and 25mm long, slightly vanadian (As0.92V0.07), in massive braunite ore in Motoyama-cho (Sasaki et al (2002). (probably the same place?).
Nagasaki: Brownish orange ardennite (a bit darker than the type locality material) occurs as macroscopically crystalline veinlets in compact massive braunite ore at the Tone mine; aggregates to over 1cm across composed of subparallel thin prismatic crystals.
ARSENIC (shizen-hi)
Fukui: At the Akadani stibnite mine (also written Akatani), arsenic forms dark grey, globular crystalline masses of concentric and radial aggregates (86.6% As, Tschermak 1897), with the polar edges of the rhombohedral crystals projected on the surface, in hydrothermally altered rhyolite (quartz liparite) now consisting mainly of clay and minor quartz. This is one of the very few localities in the world for native arsenic crystals, and they are still collectable here after heavy rain washes away more clay. Cleaned crystals and fresh fracture surfaces are steel grey, but they blacken within hours of contact with air. These crystal balls rattle around loose in vugs in the matrix, so specimens in collections tend to consist of matrix-free isolated balls although, when in matrix, they may be associated with fibrous stibnite, quartz, pyrite, minor realgar or earthy secondary arsenic oxides. Typically 7 to 15mm diameter; balls over 2cm diameter are very rare, but exceptional specimens even reach 5cm diameter! Apart from the well-known spheres, cuboid habits with depressed centers occur, inferred to be subparallel aggregates of rhombohedra. Also rare single rhombohedra to 1cm. The spiky crystal balls, known to Japanese collectors as "konpeitou-ishi" after 'confitte' sugar crystal ball candy, were depicted in TschermakÕs 1915 "Lehrbuch der Mineralogie" and became classic specimens now distributed in collections worldwide. Native arsenic also occured rarely as fine-grained dark grey masses at Sotomo.
Ouita: Concentric spheroidal arsenic masses form botryoidal aggregates or single nodules to over 5cm diameter at the Mukuno (Mukeno) mine, in drusy quartz-lined vugs in a Au-Ag-bearing quartz vein cutting native arsenic-stibnite-bearing Miocene andesitic tuff and andesite. Easily weathers to claudetite and kankite. Some arsenic nodules are surrounded by a shell of massive stibnite. Very rarely with para-arsenolamprite.
ARSENIOPLEITE (ahseniopurei-seki)
Fukushima: Rare, at the Gozaisho mine as brown crystals or grains to a few mm size, in rhodonite ore, sometimes with braunite and langbanite.
ARSENOLITE (hoh-hiso-ka)
(Some excellent reputed arsenolite specimens from Japan, with octahedral white crystals to 7mm, are anthropogenic; produced by burning realgar.)
Saitama: Chichibu mine.
ARSENOPYRITE (ryuu-hi-tekkoh)
Aichi: Isolated double-terminated short prisms of rhombic shape to 2cm (usually only 7mm), showing mainly (110) and (014) faces, some as star-shaped penetration twins, occur embedded in soft clay-like sericite in an epithermal pyrite-stibnite-quartz vein at the Iname (now Furikusa) mine. Specimens are distributed in collections worldwide, and usually consist of loose floater crystals or aesthetic crystal groups. Originally mined for Au-Zn-Pb, but now mined for sericite for the cosmetic industry, and the arsenopyrite is a hindrance. At the neighboring Awashiro mine, isolated well-developed short prismatic crystals from 4 to 8mm are disseminated in hydrothermally altered Tertiary liparite tuff. Most commonly forms flat rhombs with a very short c-axis, less commonly more elongated prisms. Some faces are striated, with a brilliant metallic luster on the non-striated faces. Subparallel aggregates may form a saddle-shaped depression. Penetration twins are common, sometimes trillings, less commonly contact twins and various other twin laws. ((probably the same ore deposit))
Gifu: At the Akatani mine, radial aggregates of acicular arsenopyrite occur in sericite; isolated xls are up to 7mm long and show basal prism faces. With ferberite (qv) in pneumatolytic quartz veins at the Ebisu mine. Also in the Tohgane mine.
Hyougo: The cobaltoan "danaite" variety occurs in a banded grey quartz vein at the Ikuno mine, with petrukite- and sakuraiite-bearing stannite.
Ishikawa: Excellent crystals, well-known to Japanese collectors, short prismatic to 5mm, associated with rhodochrosite rosettes, chalcopyrite, pyrite, galena and sphalerite in cavities in massive sulphide ore at the Kuradani mine.
Kagoshima: Very abundant at the Yunagano Ag-Au mine, where it constitutes 90% of all sulfides present, although only as tiny crystals less than 0.1mm long in banded and brecciated quartz veins.
Mie: Small sharp euhedral crystals, commonly as penetration twins, at Inukai. Perfect short prismatic crystals, often as penetration twins, at Aratsuchi ((Mie-ken??)).
Miyagi: One of the principal ore minerals at the Matsuiwa As-Cu-U mine, hosted in early Cretaceous altered andesites and pyroclastics.
Miyazaki: Aggregates of poorly-developed rhombic crystals in Takachiho (Toroku mine). Arsenopyrite at the Shika Sb-Au mine, fine-grained prismatic crystals to 0.7x0.1mm, is apparently auriferous, yielding 23g/t Au, despite no gold-bearing inclusions detectable by ore microscopy. The major ore mineral in high-temperature quartz veins at the Matsuo mine, where it was mined to produce arsenious acid. Also the most abundant sulfide at the Ouchi silver-antimony mine, but only as quite fine-grained: euhedral short prisms to 0.5mm diameter.
Nagano: Cobaltoan arsenopyrite in massive ore in gabbro was worked at the Tenryu Co-Ni mine.
Nara: Cobalt-bearing arsenopyrite ("danaite") occurs with quartz and pyrite at the Dougatani mine. Specimens are still found there by Japanese collectors on the steep, forested dumps, along with secondary erythrite. Arsenopyrite also from Harimichi.
Okayama: In vugs in crystalline quartz in a contact metasomatosed copper deposit at the Yoshioka mine, arsenopyrite forms good prismatic or tabular rhombic xls to 2cm, showing (110) and (101) faces, associated with calcite and chalcopyrite. Crystals usually in groups, but never with saddle-shaped depressions, rarely as isolated crystals. Some faces heavily striated, others smooth. As masses together with loellingite, andradite, johnbaumite and calcite in a vein cutting marble at Fuka.
Ouita: The Obira Sn-Cu mine produced some of the worldÕs most spectacular arsenopyrite specimens - sharp prismatic crystals to 30cm(!) long (Koh collection, Kyushu University), elongated on the b-axis, with well-developed (110) and terminal (001) faces, and smaller (100) and (101) faces, crystals sometimes organized in subparallel radial aggregates or hemispheres, in enormous vugs (to several cubic meters!) in quartz, associated with fluorite, quartz, cassiterite, pyrite, sphalerite and acicular tourmaline as products of pneumatolytic metasomatism. Arsenopyrite crystals 5 to 10mm long, with small quartz crystals at Hasegawa.
Saitama: Good quality, simple sharp equant crystals to a few mm size at the Chichibu mine. Well-represented in japanese collections.
Tochigi: Excellent crystals from the Ashio mine are well-known to Japanese collectors. Short prismatic or tabular xls with (110) and (014) faces occur in drusy cavities in hydrothermal replacement chalcopyrite ore. Earlier, higher temperature, crystals show shorter prismatic habits than the longer, younger, lower temperature crystals.
Wakayama: Cobaltoan arsenopyrite was worked for cobalt in 6 quartz veins at the Taisho mine north of Shingu (in the Wakayama exclave between Mie and Nara prefectures??).
Yamaguchi: Abundant in scheelite-rich skarn at the Kiwada mine as sharp, striated xls to 2cm, some as v-shaped twins. Aggregates of small granular xls in massive quartz at the Tawarayama mine. Abundant in hornblende-biotite granodiorite in the western part of the Hobenzan granitic complex.
Yamanashi: Short prismatic xls to 1cm, showing (110) and (014) faces, occur with the famous quartz crystals in pegmatitic quartz veins at the Otome mine. Large quantities occurred at the Suzukura Cu-Zn-Pb mine, and at one time were used for commercial production of arsenic. Cobaltoan arsenopyrite in network veinlets disseminated in granite was worked as cobalt ore in the Horai mine.
ARSENOSULVANITE (hi-suruban-koh; hi-ryuu-banajin-dohkoh)
Akita: At the Osarizawa gold-silver-copper-lead-zinc mine, arsenosulvanite is disseminated as microscopic grains in massive copper sulfides. The arsenosulvanite-bearing patches tend to decompose more rapidly than other parts of the ore, lending a bluish cast to the surface due to the formation of a thin film of "vitriol". "Arsenosulvanite" from here is widely distributed in systematic species collections, with the collectors often not realizing that the mineral is invisible.
ARUPITE (aruupu-seki)
Mie: This Ni-analogue of vivianite was found on Suga-shima, in a small Cu-Ni orebody that was not discovered until the mid-1980s.
ASBOLANE (ASBOLITE) (gosu-do)
Aichi: The "asbolite" reported from Seto city, where it forms part of the cementing material in a conglomerate, is actually a cobaltoan lithiophorite (qv) with only 0.5% Co.
Nagasaki: Asbolane at the Gotoh mine contains 10% Co, indicating a borderline true asbolane. This ore (as well as other Co-bearing Mn oxides) was called "gosu-do" in ancient times and was used to give a blue color to ceramic glazes, although the color was diminished by the impurities present.
ASPIDOLITE (IMA # 2004-049) (sohda-kin-unmo)
Gifu: Interleaved with its K-analogue, phlogopite, in thermally metamorphosed (contact aureole) hornfels in Kasuga-mura (at Mitsuka?), the first locality from which this mica group species, which has also been called "natrium-phlogopite" or "sodium phlogopite", was properly described. Light brown in hand specimen. (Pleochroic: colorless with yellowish tint; pale yellowish brown.) The interleaved aspidolite-phlogopite aggregates are surrounded by phlogopite rims. Associated with pargasite-magnesiosadanagaite, titanite, calcite, scapolite, apatite, pyrrhotite, chalcopyrite. A representative analysis corresponds to (Na 0.90, K 0.10) (Mg 2.27, Al 0.41, Fe'' 0.23, Ti 0.05) (Al 1.44, Si 2.56) O 10 ((OH) 1.97, F 0.03). Two polytypes were identified here: aspidolite-1M and aspidolite-1A.
ATACAMITE (atakama-koh; atakama-seki)
Kagoshima: As green crusts to over 6cm across, associated with blue connellite and abundant green paratacamite, at the ruins of an old copper mine on the 1km-wide uninhabited Futago island.
Tokyo: Fumarolic atacamite formed on lava surfaces of the 1983 eruption on Miyake island. Associated with tenorite. Similarly reported from Izu-Ohshima as cm-size light green fumarolic crusts on highly vesicular scoria. (Confirm correct volcano???)
Wakayama: Atacamite is collectable as bluish green crusts and films on black crusts coating boulders of light-coloured rock exposed to the waves on the beach at Taiji, where it provides a wet collecting experience. Formed by reaction with chloride ions in seawater.
Yamaguchi: Bright grass-green porous crusts to 20cm across and 1 or 2mm thick, in fissures in granitic rock from the Shizuki mine.
AUGELITE (rin-bando-seki)
Yamaguchi: Reported in 1999 as a mixture with trolleite, forming pseudomorphs, possibly after berlinite, at the Hinomaru-nako mine.
AUGITE (futsuu-kiseki; titanian augite = chitan-kiseki; Mn-Fe-rich augite ("urbanite") = uruban-kiseki)
(NB: As currently defined, Ca-Mg-dominant pyroxene, "augite", is merely an impure variety of diopside (qv) and doesn't really deserve species status. "Ferroaugite" (qv), on the other hand, Mg-Fe-dominant, should be considered a separate species, even though not recognized as such. This illogical nomenclature tangle needs revision.) (Qv also pigeonite.)
Aichi: The manganoan variety "urbanite" in metasedimentary Mn ore at the Taguchi mine.
Fukuoka: Manganese-bearing "urbanite" occurs at Misaka pass.
Fukushima: Manganese-bearing "urbanite" occurs at the Ishikawa mine. "Subcalcic ferroaugite" (DHZ) from Ohkuboyama (qv Ferroaugite). In the central Abukuma plateau, the clinopyroxenes in regionally metamorphosed rocks change from salitic (diopside) to augitic with increasing grade of metamorphism.
Hokkaido: Titanian augite occurs with plagioclase and ilmenite in alkali dolerite on Rebun island.
Ibaragi: In amphibolite in Sekimoto-mura, Taga-gun. (Ca 0.872, Mg 0.572, Fe'' 0.437, Fe''' 0.048, Na 0.032, K0.032, Al 0.018, Mn'' 0.016, Ti 0.015) (Si 1.909, Al 0.091) apfu.
Iwate: A manganoan variety, "urbanite", occurs at the Noda-tamagawa mine, as 2cm dark honey-brown cleavages embedded in pink rhodonite; and with richterite and manganoan phlogopite in hornfels. (NB: The so-called "PICROURBANITE" from here is described under "aegirine", but might be mis-classified.)
Kagoshima: Violet-brown translucent, prismatic xls of titanian augite weather out of dark andesitic lava on the coasts of Suwanose island. In pyroxene andesite lava on Iou island, with roedderite, hypersthene and anorthoclase.
Kumamoto: Abundant as a constituent of andesite lavas at many places, including Goou-tohge and Ishigami-yama, associated with magnesiohornblende and hypersthene. Dark chocolate-brown short prisms to 8mm, as euhedral or intergrown crystals with octagonal cross-section, on Kanmuri-dake (Kanmurigatake) (SW edge of Aso caldera).
Nagano: Black, short prismatic augite crystals to 1cm occur on Tateshinayama (Tadeshina volcano) as floaters weathered from andesite. Also on Yatsugatake. Brownish black short prisms to 7mm on Mt. Iimori.
Nagasaki: As pyroxene nodules in trachybasalt at Numazu on Iki island. (Ca 0.812, Mg 0.775, Fe'' 0.150, Al 0.099, Fe''' 0.087, Na 0.047, Ti 0.032, Mn'' 0.003, K 0.002) (Si 1.782, Al 0.218) apfu.
Niigata: At Yoneyama volcano, as black, short prismatic xls and twins to 1cm, as phenocrysts in olivine-augite andesite.
Saga: Green, short prismatic euhedral "floater" crystals to 1cm, often twinned on (100), weather out of decomposing basalt at Nishigatake in Imari city. Some are rather rough-surfaced, but many are surprisingly sharp and lustrous, with color varying from blackish green to olive-green to "chrysoberyl"-green. "Titanaugite" occurs as crystals to 2mm in volcanic vugs at Yunoo.
Saitama: Chromian augite forms phenocrysts (resembling those from mantle peridotite) in basalt and limburgite in the Mikabu greenstones of the Ogose-machi area and the Chichibu terrain greenstones of the Ogano-machi area.
Shizuoka: In basalts and basaltic tuff at Wadaki, with hypersthene, olivine and diopside. The "augite" recorded (DHZ) from olivine basalt on Hatsushima (off the coast of Atami city) corresponds more closely to pigeonite (qv).
Tokyo: As phenocrysts with olivine and plagioclase in basalt dikes and breccias on Mukoo island in the Ogasawara chain. As phenocrysts in the high-Ca boninite ("augite boninite") rock of Chichijima (type locality of the rock type "boninite"). Augite-olivine trachyandesite on Iwojima. The "subcalcic augites" (DHZ) from Ohshima island seem to correspond more closely to pigeonite (qv) or "ferroaugite" (qv).
AURICHALCITE (sui-aen-dohkoh)
Shiga: Beautiful sky-blue silky radiating mammilary crusts to 12mm across, and isolated pustules, occur in drusy quartz-lined vugs on white skarn rock in a quarry on Haiyama hill, sometimes associated with devilline or serpierite.
Shizuoka: Pale green to greenish blue, silky to pearly, in vuggy quartz and limonite at the Kawazu mine, sometimes together with azurite.
AUTUNITE (rinkai-uran-koh; rinkai-uran-seki)
Okayama: Yellowish green scales and films to 1cm on brown limonitic stains, as a common secondary ore mineral in oxidized ore at the Ningyoh-tohge uranium mine. Disseminated in the sandy matrix of Pliocene lacustrine basal conglomerate; also as thin films on the surface of, and in fractures in, the pebbles in this conglomerate. Also as light lemon yellow earthy films to several cm, and thin scales, on fissure surfaces in the granitic rock here. Fluoresces brilliant yellowish green and is highly radioactive. In collections, generally dehydrated to meta-autunite. This deposiit was discovered in November 1955 by radiometric surveys carried out from an automobile. Mining started shortly thereafter with autunite as the principal ore (but ningyoite later became the most important ore mineral when unoxidized zone was reached).
AWARUITE (awaruwa-koh)
Kouchi: Together with the very similar looking wairauite in serpentinized ultrabasic rocks at Okoh.
Nagano: Small grains embedded in veinlets in peridotite from Oshika-mura, usually mislabelled "native iron" in collections, are actually awaruite or iron-rich native nickel. Analysis shows 43.5 wt% Fe, 56.5 % Ni, empirical formula (Ni 0.56, Fe 0.44). Not surprisingly, they are much less prone to rusting than real native iron.
AZURITE (ran-dohkoh)
Akita: In the oxide zone of the Kisamori copper mine, small tabular azurite crystals are associated with fibrous cerussite aggregates and botryoidal malachite incrustations. At the Hisaichi copper mine, it occurs as tabular xls with large (001) faces. Also in the large limonitic oxide zone of the Osarizawa mine.
Okayama: Thin crusts of minute azure-blue xls associated with malachite occur on limonite covering oxidized copper ores in a contact deposit at the Mihara mine. Thin blue crusts at the Hiyoshi mine.
Shizuoka: Deep blue tabular xls to 1cm, showing (001), (221), (110) and (100) as principal faces, are associated with thin incrustations of malachite in cavities in a sphalerite-quartz vein at the Rendaiji (Kawazu) mine. Small clusters and aggregates of microcrystals are still found in vuggy quartz and limonite on the dumps, often associated with aurichalcite.
Toyama: Azure-blue translucent tabular crystals at Kamegatani.
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