Encyclopedia of Japanese Minerals (Go to Intro Page)
by Alfredo Petrov
Minerals Starting with "B"
BABINGTONITE (babinton-seki)
Fukushima: Babingtonite is found at the Yaguki mine as black crystals with brilliant luster, forming veins and irregular masses in hedenbergite-garnet-chalcopyrite-magnetite skarn at a contact with granodiorite. Babingtonite from the Yaguki mine exhibits abnormal optical properties (Mineralogical Journal 3, 236-245 (1961); Amer.Journ.Sci. Ser.5, v.4, 159-164 (1922)). Strongly pleochroic in thin section: deep emerald green, purple brown, deep brown. Crystal faces include (102), (201), (111), and possibly (023).
Shimane: At Kouragahana, square black crystals to 4mm, in basalt vugs, associated with colorless spheres of thomsonite on pale green prehnite. Frequently seen as aesthetic specimens.
BAGHDADITE (bagudaddo-seki)
Iwate: In skarn at the Akagane mine; first recorded locality (1999) in Japan.
Okayama: In spurrite as colorless vitreous grains, or rare short prismatic crystals to 1mm, with yellow-orange SW UV fluorescence, embedded in spurrite skarn with hydrogrossular and bicchulite at Fuka (but not found in the violet spurrite there).
BAKERITE (behkah-seki)
Okayama: At Fuka, with kusachiite, sillenite, tenorite, bultfonteinite and henmilite in calcite vein at contact between limestone and gehlenite-spurrite skarn. Greenish prismatic crystals to 1cm.
BARATOVITE (baratofu-seki) (qv "KATAYAMALITE")
BARITE (juushoh-seki; plumboan barite = hokutoh-seki)
Akita: Colorless transparent, tabular rhombic barite crystals to 7cm, showing (210), (001), (101), (010) and (011) faces, occur at the Kosaka mine in drusy parts of the massive pyrite-galena-sphalerite kuroko-type Motoyama orebody. Transparent white, tabular rhombohedral xls in cavities in a chalcopyrite-pyrite-bearing quartz vein at the Nagaki mine. Transparent white, tabular xls showing (001), (210) and (101) faces, with younger scalenohedral calcite xls, in vugs in pyrite-sphalerite-bearing quartz vein at the Edate mine. Good white transparent, tabular xls to 9cm(!), showing mainly (001) and (210) faces, bevelled by small (101), (310), (011), (010) and (211) faces, are associated with pyrite, chalcopyrite and sphalerite in quartz vein cavities at the Osarizawa mine. Complex barite crystals to 4.5cm long, 7.5mm thick, with a prominent c-face showing zoning, covered with earthy brown Fe oxides in vugs in a barite vein in a tunnel between the Osarizawa and Akazawa mines. In the Akazawa mine itself, barite xls to 1cm wide and 1.5mm thick, of simple habit, with a blackish coating on the c-face, occur on quartz and marcasite in the Tatsuana lode. Cavities in kuroko-type massive sulfide ores at the Hassei (Tsubaki) mine produced large quantities of excellent transparent colorless or pale yellow to pale yellowish orange barite as elongated tabular crystals over 5cm long, with prominent (100), (001) and (210) faces, and minor (010), (011) and (101) faces; c-faces are lustrous but uneven; a-faces dull and vertically striated. Larger crystals translucent white. Barite at the Arakawa copper mine forms rosettes of colorless transparent, rhombic tabular crystals to 7mm, associated with malachite in cavities in a chalcopyrite-quartz vein. On the hanging wall, associated with brownish white, massive earthy "apatite". Also as epimorphs after chalcopyrite. Barite here can also be pseudomorphed by quartz (qv) or chalcopyrite. Barite was also pseudomorphed by quartz at the Ani mine, but these pseudos were neither as abundant nor as sharp as those from the Arakawa mine. The Ani mine also had rhombic tabular barite crystals of simple habit, not pseudomorphed. Transparent white, rhombic tabular barite xls reach 12cm(!) at the Komakizawa mine, in cavities in a chalcopyrite-sphalerite-pyrite-bearing quartz vein. The Innai mine produced white translucent crystals of simple rhombic tabular habit with c and m faces. Also in kuroko ores from the Hanaoka mine and the Fukazawa mine. "HOKUTOLITE", a lead-rich variety of barite, is being precipitated from strongly acidic hydrochloric and sulfuric waters at the mouth of Tamagawa Hot Springs (Shibukuro river) as banded alternating pale brownish white, light brown, yellowish brown and pale reddish brown crusts, individual bands from about 0.1 to 2.5cm thick, composed of pale yellow translucent rhombic platy, short prismatic or acicular crystals several mm long. Lead content varies widely between differently colored bands: 0.088 to 0.195 apfu in pale brownish platy crystals, 0.008 in white rhombic-prismatic crystals. A little strontium (0.07<1.79 wt% SrO) is also present in these Pb-bearing barites. Traces of radium replace barium, making young hokutolite mildly radioactive. (This was the world's first locality for Pb-rich barite (Sakurai, 1898), but it was named for the even more Pb-rich material (0.311apfu) found in 1899 at Hokutoh hot springs in Taiwan.) The Tamagawa crusts are estimated to grow at 7mm per year, and were declared a national monument in 1952, prohibiting further collecting. More weakly lead-bearing barite (Pb 0.031 to 0.040 apfu, ~ 3% PbO), likewise radioactive, occurs as pale brown to light grey, rhombohedral short-prismatic or platy xls to 1cm, showing (001) and (210) faces, forming veins in altered andesite at Kawarage hot springs.
Aomori: Thin tabular, colorless xls to 5cm or more in vugs in galena-jordanite vein at the Yunosawa mine. Also at the Abeshiro mine. Transparent platy crystals, with inclusions of black mud and yellow-grey orpiment spherules, are found in lacustrine sediments argillized by acid water in Osorezan caldera. A first stage of rapid growth produced dendritic barite, followed by slower overgrowth in the more usual parallelogram habit. Colorless to whitish, thin tabular barite crystals to 1.5cm, with dufrenoysite (qv) inclusions, or with baumhauerite, in kuroko-type ore at the Okoppe mine.
Chiba: In Paleocene andesite at Nagasakibana.
Fukui: At the Omodani mine, grey transparent, tabular xls to 1cm, with combinations of (001), (101) and (210) faces, in vugs in pyrite-chalcopyrite-bearing quartz vein.
Gifu: Forms veinlets with neotocite, cutting fine-grained hausmannite-carbonate-bementite metasedimentary Mn ore at the Nagashima mine. Quartz (qv) epimorphs after vanished barite crystals to 5cm at the Kamioka mine.
Hokkaido: Tabular crystals occur in association with native tellurium in fine-grained porcelanous quartz in epithermal gold-silver ore at the Teine mine; also here as transparent light brown to colorless, thin tabular xls to 12mm, associated with drusy tetrahedrite xls in a barite-quartz vein. Drusy quartz epimorphs after vanished barite crystals to 9cm (National Science Museum) once occured here. "Barite Hill" at the closed Katsuyama mine produced colorless, simple tabular xls to 4cm wide and 1cm thick, dominated by large (110) and (001) faces, from network barite veins in sedimentary rock. Fairly pure barite was mined here. Tabular barite crystals occur on quartz crystals in vugs in a rhodochrosite vein in the Inakuraishi mine. Also from kuroko-type ore at the Mogari barite mine. Exceptional specimens of blue tabular crystals to 12cm in parallel growth - locality????? (Mogari mine??). Barite was mined from replacement deposits in Tertiary volcanics at Otaru-Matsukura and at Minami-Shiraoi. Crystals over 5cm size from the Akaiwa mine. Rhombic tabular crystals, often coated with a thin earthy crust, at Ponshikaribetsu. Barite forms pale grey to white spheres and ovoid concretions to 3cm at 3,360m depth in the Chishima trench (42 56' N; 146 20' E).
Hyougo: Sharp epimorphs of chalcedony after barite crystals to 4.5cm from the Nakase mine. (qv quartz)
Ishikawa: In cavities in pyrite-chalcopyrite-bearing quartz vein at the Kuradani mine, as transparent to opaque, colorless to dark grey or blackish, rhombic-tabular xls to over 5cm, sometimes truncated on the acute angles, exhibiting c, m, u, o, d and other faces. Some crystals are concentrically zoned with light and dark bands, and sometimes thin reddish layers. Dark grey color is caused by plumose jamesonite inclusions. At the Nabeto copper mine, colorless transparent, rhombic tabular xls were found on crystalline quartz. Thin platy, opaque white xls to 5cm at a mine in Komatsu city.
Iwate: The Okinazawa mine produces aggregates of white to pale grey, tabular rhombohedra with combinations of (001), (210), (011) and (101) faces.
Kyoto: Kuroko-type veins in Paleozoic slate were mined for fairly pure barite long ago at the Kasatori mine (famous for its allophane specimens), but all remains of this operation have disappeared.
Miyagi: At the Shichirizawa copper mine, barite forms rhombic tabular xls with (001), (101) and (210) faces in quartz vein druses.
Nagano: Together with albite and braunite replaces older rhodonite at the Hamayokogawa mine. Also with albite, quartz and rhodonite in rhodochrosite-rich veinlets cutting braunite-rhodochrosite ore.
Niigata: The Sado (Aikawa) gold-silver mine, especially the Takatoh-jiki site here, was a classic locality for well-crystallized barite specimens. Barite occurs in cavities in an epithermal quartz vein as transparent to translucent, pale green to pale yellow crystals to 13cm, either tabular with prominent (001), and well-developed (101), (210) and (011) faces, or as elongated prisms with just (101), (210) and (011). The c-faces are finely striated parallel to the sides. Compound crystals form from numerous subindividuals. Sometimes with pink manganocalcite. Nakayamatouge was another important locality for well-crystallized barite. It occurs as the cementing material in crevices of sandy clay nodules in Miocene sediments, and as loose elluvial crystals. The faces m, d and o are the most prominent, with a large array of rarer faces, dulled by abrasion in their sand matrix. Crystals are transparent, colorless to pale yellow, elongated along the a-axis, with only one end developed, showing that they were probably detached from site of original growth. Milky white, tabular rhombic crystals to 6cm, showing c, m, d and o faces, with chalcopyrite at the Kusakura copper mine. Crusts of small crystals with enargite and pyrite at the Hokuetsu mine.
Okinawa: Barite is presently being microbially deposited as the major mineral on sediments around the undersea vents of the "Jade" hydrothermal field (Izena Cauldron), with sphalerite, orpiment and other sulfides. The barite is normally coarse granular, porous, irregularly shaped fragments, cream to grey. Also as rosette-like clusters of subhedral to euhedral xls, often orange from orpiment inclusions, or olive-green from a fine dusting of clays.
Shiga: As crystals embedded in hausmannite-manganosite-carbonate ore at the Ioi mine, and as barite-neotocite veinlets, lined with bementite along the edges, traversing alleghanyite-galaxite-hausmannite ore.
Tochigi: Quartz (qv) pseudomorphs after barite at the Tomii mine.
Yamagata: Barite was mined at Yoshino, a kuroko-type deposit with pyrite, sphalerite, chalcopyrite, gypsum and quartz.
Rikuchuu: (Which prefecture???) Colorless transparent, simple rhombic tabular crystals with c, m and d faces, on pyrite at Komaki.
BAUMHAUERITE (baumuhaueru-koh)
Aomori: Long prismatic, longitudinally striated lead-grey crystals to about 1mm at the Okoppe mine, in vugs in fine-grained granular pyrite masses, and between thin tabular barite crystals. Not distinguishable from the dufrenoysite here without XRD.
BEMENTITE (bemento-seki)
Gifu: Irregular patches of cryptocrystalline material, reportedly bementite, in metasedimentary Mn ore consisting of a fine-grained mixture of hausmannite and carbonate, and in numerous younger barite-carbonate-neotocite veinlets, at the Nagashima mine.
Hokkaido: With okhotskite in Mn-bearing hematite ore at the Kokuriki mine.
Kouchi: A major ore mineral, with rhodochrosite, at the Ananai mine. Bementite is the main component of the "katsuo-bushi" ore here (named after the hard brown horn-like dried bonito fish used in Japan as a condiment). The "tosalite" (qv) from the Ananai (Niro) mine was at one time considered to be ferroan bementite, but this is in doubt. Also from Kunimiyama.
Mie: Brown translucent waxy-looking patches to 2cm, embedded in pink manganese ore at the Kurihara mine.
Shiga: As veinlets formed of minute crystals, connecting and terminating at patches of hausmannite in alleghanyite-carbonate ore at the Ioi mine. Also lining the edges of barite-neotocite veinlets crossing alleghanyite-galaxite ore. The largest xls are sheets about 0.04mm wide. Slightly dichroic light brownish yellow and dark brownish yellow; RI 1.61; D 3.15.
Yamaguchi: Minute yellowish crystals of probable bementite, with carbonate and neotocite, form late veinlets cutting quartz-carbonate-pyroxmangite Mn ore pods in metachert at the Renge mine. (RI 1.63; optically -, very small optic axial angle.)
BENITOITE (benito-seki)
Niigata: Benitoite occurs as colorless to whitish, tabular crystals to 0.5mm, and anhedral grains to 2mm, fluorescent brilliant blue-white under SW UV, at Kanayamadani, Hashidate, with albite, magnesioriebeckite, quartz, strontio-orthojoaquinite and rare ohmilite in riebeckite-syenite or albitite rock enclosed in serpentinite. Perhaps more common here than generally thought, but not often collected because in daylight the benitoite is almost impossible to distinguish from the host albite, and few Japanese collectors use ultraviolet lights. Extremely rare triangular light blue crystals (much paler than the classic California ones) up to 5mm have also been found here.
BENJAMINITE (benjamin-koh)
Hyougo: Selenian benjaminite occurs with selenian matildite at the Ikuno mine, in Au-Ag mineralization in the polymetallic zone. Analyses correspond to formulae (Ag 2.74, Cu 0.24) (Bi 7.00, Sb 0,01) (S 10.89, Se 1.12) for a sample from the Nanten vein, (Ag 2.90, Cu 0.10) (Bi 6.74, Pb 0.18, Sb 0.07) (S 11.68, Se 0.33) from the Daimaru vein (Shimizu, M. (1998) Resource Geology 48, 2, 117-124).
BENLEONARDITE (benreonarudo-koh)
Shizuoka: Bismuthian benleonardite is reported from the Kawazu mine, but needs confirmation.
BERAUNITE (beraun-koh)
Hyougo: Greenish grey acicular crystals about 0.1mm form sprays in altered vivianite (qv) nodules from upper Pliocene clay bed at Katada, with analysis showing 0.94% CaO (= 0.15 apfu Ca), 0.23% MnO (= 0.03 apfu Mn). Blackish brown crystals as 2 to 3mm furry aggregates in 2cm limonite nodules from upper Pliocene clay in Kita-ku in Kobe city. Also in this clay formation, in a Seishin-Chuhou roadcut at Oshibedani, as an alteration of vivianite nodules to 3cm diameter.
Ibaragi: In a phosphate pegmatite intruding pelitic schist in a quarry at Yukiiri.
BERNDTITE (berunto-koh)
Hokkaido: Occurs as microscopic inclusions with toyohaite (qv) and herzenbergite at the Toyoha Pb-Zn-Ag mine, in a banded hydrothermal chalcopyrite-sphalerite vein cutting massive pyrite-spalerite ore.
BERTRANDITE (berutorando-koh)
Gifu: At Tawara, tabular crystals to 6mm with beryl from miarolytic cavities in granite quarries. Usually seen in collections as loose, twinned colorless crystals to only 1 or 2mm.
Ibaragi: As microcrystals with beryl in granite pegmatite at Yamanoo.
Kyoto: Microcrystals are still often collected on the dumps of the Gyouja-yama scheelite-pyrite-beryl-bearing quartz veins.
BERYL (ryokuchuu-seki)
Fukuoka: Pale yellowish green, massive beryl aggregates are found in granite pegmatite at Nagatare.
Fukushima: At Wagu and Suishouyama and other granite pegmatites of the Ishikawa district, sometimes with columbite. Crystals up to 50cm are reported (Geological Survey, 1970). Pale green translucent, simple hexagonal columnar xls reach 9cm long and 8cm diameter at Tomaki. At Ishikawayama in this district, transparent pale yellowish green to light bluish green, simple columnar xls to 7cm long and 5cm wide. At the Uzumine feldspar mine, as clear pale blue anhedral masses to 2cm, associated with yellow chrysoberyl in a columbite-bearing pegmatite.
Gifu: In the Naegi-Hirukawa district, transparent pale green, prismatic xls to 3cm, striated parallel to the c-axis. Also rarely in the granite pegmatites at Tawara, and in the Fukuoka mine, as short to long prismatic, gemmy pale green to light blue aquamarine xls to over 6cm long, from which facetted gems to 10mm have been cut. (During WWII, the Furukawa company mined beryl at the Fukuoka mine to produce beryllium metal for JapanĠs incipient atom bomb project.) A few Hirukawa district beryls, although from granite pegmatite, contain a little trivalent chromium and are green enough to be considered "emeralds". Transparent pale bluish xls averaging 1cm long, in quartz vein cutting granite pegmatite at Kaminagi.
Ibaragi: At Yamanoo, transparent greenish white or pale green, prismatic xls to 4cm long, 6mm thick, with either flat or modified basal faces, are associated with quartz, muscovite, microcline and tourmaline in granite pegmatite. Also elsewhere in the Tsukuba district. Pale blue non-transparent crystals to 15cm(!) at Yukiiri.
Iwate: With elbaite and lepidolite in a short-lived pegmatite mine at Sakihama.
Kagoshima: In "pegmatitic" wolframite-tourmaline-Bi-Au-bearing quartz veins cutting Mesozoic slate metamorphosed by the Tertiary Yakushima granite intrusion at the Miyanoura mine on Yakushima island.
Kyoto: Colorless acicular beryl crystals are not uncommon in vugs in the scheelite-bearing quartz veins on Gyoujayama.
Saga: Pale blue transparent aquamarine occurs as crude crystals embedded in pegmatitic quartz vein in biotite granite at Sugiyama.
Shiga: Transparent pale green, columnar xls to 3cm long, in vugs at Tanokamiyama, in granite pegmatite.
BETAFITE (betafo-seki)
Fukushima: At Ippaizan in the Abukuma massif (Omori, K. et al. (1960), Science Reports of Tohoku University, v. 6, 380).
BETA-SULFUR (behta-shizen-i'ou)
(At ordinary temperatures, these crystals are paramorphs of normal alpha-sulfur after beta-sulfur.)
Hokkaido: Thin prismatic crystals, elongated on [001], with a(100) and m(110) prism faces, small c(001) terminations bevelled by small q-faces, were found in the 1936 sulfur lava flow which became the Shiretoko mine.
Iwate: Honeycomb-like aggregates of thin prismatic crystals to 1cm at the Tsurugiyama mine.
Miyagi: Transparent yellow paramorphs of alpha-sulfur after beta-sulfur are associated with the normal pyramidal monoclinic sulfur crystals on loose stones around fumaroles at the Narugo mine. The beta-sulfur crystals vary from long prismatic, elongated on [001], contact twins with twinning plane on (100), to thick tabular parallel to [010].
BETA-URANOPHANE (behta-uranofen)
Tottori: Pale orange-yellow films or earthy yellow aggregates of short-prismatic, euhedral microcrystals partly replace wood buried in the sandy matrix of a Pliocene lacustrine basal conglomerate at the Tohgoh mine on the northern rim of the Ningyoh-tohge mining district. Highly radioactive.
BICCHULITE (bicchu-seki)
Iwate: Black massive bicchulite occurs with dark grey tilleyite (qv) and pale green vesuvianite in marble at the contact between limestone and a gabbro intrusion in the Sakae orebody of the Akagane mine. The bicchulite also forms pseudomorphs after a tetragonal mineral, probably gehlenite (as at the type locality).
Okayama: The type locality for this Ca-Al-silicate is Fuka, where it formed by hydration of gehlenite in skarns. Bicchulite forms colorless vitreous grains with no cleavage, intimately associated with hydrogrossular, gehlenite, schorlomite and vesuvianite in whitish to grey-black masses and sharp pseudomorphs after blocky gehlenite crystals, usually collected standing out of the matrix after weathering away of the less resistant calc-silicate rock. When first collected, usually stained brown by soil organic matter.
"BIOTITE" (kuro-unmo) (Generally = intermediate phlogopite-annite (qv) series; Most japanese "biotite" turns out on analysis to be phlogopite, with some very Fe-rich ones = annite, and some Mn-rich ones might perhaps = shirozulite; less well determined biotite series material is listed here.)
Fukuoka: Daisen.
Fukushima: On Suishyouyama. Reported as both "biotite" and "lepidomelane" in Ishikawa district pegmatites.
Gifu: Naegi district.
Shiga: Loose crystals as stout hexagonal prisms from 4 to 10mm weather out of tonalite at Inohana. Greenish black, but commonly display a golden sheen on the cleavage face. Also around Tanokamiyama.
Yamaguchi: Biotite contains over 3 wt% fluorine in skarn-hosted scheelite deposit at the Kuga mine.
BOEHMITE (behmu-seki)
Hyougo: Boehmite occurs in kaolin at the Ebara (Ehara) mine, with analysis showing impurities (as wt% oxide) Si 2.95, Fe'' 0.72, Ca 0.14, Ti 0.04, Mg 0.02 (T. Ota & T. Yamamoto analysis, 1957; in DHZ).
Okayama: Pale tan, waxy massive boehmite, containing light orange "rice grains" of sudoite, at the Itaya mine. Also in the Mitsuishi mine.
BOGDANOVITE (bogudanofu-koh)
Iwate: A copper-rich gold exsolution phase in chalcopyrite-cubanite ore in skarn at the Kamaishi mine, reported in the literature as "4:1 type cuprous gold", with composition Au78Ag3Cu19, might be bogdanovite.
BOLIVARITE (boribah-seki)
Tochigi: Scarce at the Ashio mine, as tiny white spherules "resembling insect eggs".
BOLTWOODITE (borutoĠuddo-seki)
Tottori: In petrified wood and carbonaceous matter in oxidized parts of an epigenetic uranium deposit in Pliocene lacustrine basal conglomerate overlying granite at the Tohgoh mine.
BORCARITE (hohkai-seki)
Okayama: As light green to pale green or almost colorless, fat spiky crystals to 1 cm at Fuka, often associated with uralborite or nifontovite or charlesite.
BORNITE (han-dohkoh)
Akita: Silver-bearing bornite is the main ore at the Furutobe mine, where it formed at very low temperatures in a kuroko-type deposit. Also abundant in kuroko-type ore at the Shakanai mine.
Ehime: At the Besshi mine, in a kieslager-type massive bedded pyrite deposit concordant with strongly folded Sanbagawa amphibolite, greenschist, graphite schist and quartz schist. Also at the Ikadazu copper mine.
Fukui: Massive epithermal bornite with chalcopyrite, galena and acanthite forms the Cu-Ag ore at the Omodani mine. Often contains rich sheets of native silver in its fissures.
Hiroshima: Bornite from the Jinmu fluorite mine shows microscopic "pseudocleavages" in 2 or 3 directions caused by included lamellae of chalcopyrite or wittichenite.
Hyougo: Massive bornite as aggregates banded with chalcopyrite, tetrahedrite, stannite and pyrite forms the ore in the xenothermal polymetallic Kanagase orebody of the Ikuno mine. Sometimes has younger calcite and native silver in its fissures. Large masses of bornite, with typical purplish tarnish, with chalcopyrite, stannoidite, and rare mawsonite at the Tada mine. Also at the Akenobe mine.
Okayama: Abundant cm-size masses of bornite in coarse-grained garnet-vesuvianite skarn at the Mihara mine. Sometimes associated with hessite, chalcopyrite and greenockite, or may contain microscopic inclusions of miharaite, chalcopyrite, galena and wittichenite.
Shizuoka: Tiny crystals of bornite are common in some of the quartz veins of the Kawazu mine. May be coated with a film of idaite.
Awa province (Tokushima or Chiba??): Kawada (massive bornite with chalcopyrite)
BOULANGERITE (buuranje-koh)
Miyazaki: At the Toroku mine. Also in rhodochrosite veins at the Tomiyama manganese mine. Two varieties at the Ouchi silver-antimony mine: radiating groups of straight needles, and as abundant fibrous felty aggregates, replacing sphalerite, galena, tetrahedrite.
Ouita: In sulphide ores of the Obira tin-lead-zinc-copper-arsenic mine. Also at the Houei tin mine.
Saitama: Boulangerite forms soft cottony aggregates filling cavities to several cm wide at the Chichibu mine, associated with white 2mm crystals of a rhombohedral carbonate (dolomite?).
BOURNONITE (shakotsu-koh)
Saitama: Good bournonite crystals as thick tabular "cogwheel" twins, with repeated twinning on the [110] plane, usually small, but sometimes up to 2.5cm wide and 1cm thick, were found in skarn at the Daikoku adit of the Chichibu mine 30 years ago, associated with ankerite, galena, sphalerite, pyrite, chalcopyrite, arsenopyrite. Less commonly as short square prismatic single (untwinned) crystals to 5mm, exhibiting (100), (010), (001), (110), (112), (011), (101), (111) faces. One analysis showed Pb 40.09, Fe 0.83, Ag tr., Zn 0.08, Mn 0.39, Cu 13.63, Sb 23.51, As 1.46, S 19.61, rem & SiO2 0.33. Only mm-size xls found nowadays.
BRANDTITE (burando-seki)
Fukushima: Forms white scales on rhodonite in metamorphosed sedimentary manganese ore at the Gozaisho mine, associated with braunite and sterlinghillite.
"BRASS" (shizen-shinchuu) (possibly = ZHANGHENGITE)
Kanagawa: As inclusions in anorthite phenocrysts in dark basaltic rock from Hakone volcano, with composition approx. Cu60Zn40.
Tokyo: Reported from Miyake island, also with the composition Cu60Zn40. (qv anorthite, copper)
BRAUNITE (buraun-koh)
Japanese braunites show considerable Ca (< 37 atom%) and Mg (< 47 atom%) substituting for divalent Mn, and lesser amounts of trivalent Fe (< 15 atom%) and Al (< 0.5 atom%) substituting for trivalent Mn.
With piemontite as Mn ore in the Sambagawa, Sonoki and Sangun metamorphic belts, Shikoku.
Ehime: The major ore mineral at the Nomura mine, with rhodochrosite and caryopilite; and also in the oxide zone here as microscopic intergrowths with takanelite and halloysite, forming irregular nodules from 1 to 15cm across. Massive braunite lenses up to 3cm thick in piemontite schist at the Sazare Cu-pyrites mine. Cuprian braunite (some of it actually abswurmbachite - 0.30 to 0.53 apfu Cu) is associated with strontian hollandite and Ba-Pb-bearing tweddillite as a nodule in Sanbagawa metamorphic belt quartz-piemontite schist (metachert) in the Saruta-gawa area (Sazare mine??) (Masaki Enami & Yasuyuki Banno, 2001).
Fukushima: Abundant ore mineral in regionally metamorphosed bedded Mn ore (mainly rhodonite) in the Gozaisho mine, with iwakiite, hematite, rhodonite.
Gifu: Braunite grains, surrounded by unknown cryptocrystalline mineral, in fine-grained quartz-rhodonite ore, with mica, in Paleozoic metachert at the Fukutomi mine. Also here with hausmannite in very fine-grained, partially oxidized manganosite in carbonate-rich Mn ore.
Iwate: Black metallic-looking, fine-grained braunite occurs with kozulite and pink rhodonite at the Tanohata mine. Also as a major constituent of braunite-rhodonite ores at the Funakozawa mine. And as massive tephroite-rhodonite-braunite-hausmannite ore at the Noda-Tamagawa mine. Also at the Fukushi mine, the Hanawa mine, and the Ohtani mine.
Kyoto: At the Ashidani mine as black layers intercalated with brown hematite-bearing tuff in banded metasedimentary Mn ore. As dark chocolate-brown bands to 1.5cm wide in reddish meta-chert in banded metasedimentary Mn ore at the Dainimachi mine.
Nagano: In bedded rhodochrosite-rich ore at the Hamayokogawa mine. Braunite pods can contain inclusions of anhedral rhodochrosite grains and be crossed by younger rhodochrosite veinlets. Associated with rhodonite, and minor quartz, barite, albite, diopside, hausmannite.
Nagasaki: Braunite was the main ore mineral at the Matsugaseko mine, where it formed lustrous granular lenses in piemontite schist country rock. The roof of this mine has collapsed and the adit is fenced off. Also as shiny black, sharp modified octahedral crystals to 2mm (exceptionally 5mm) in white to brown matrix (quartz?) at the Tone mine, where it was the main component of braunite-piemontite Mn ore. With piemontite at the Ouishitone mine (same place??). Also at the Mie mine and the Muramatsu mine.
Tochigi: Common in the Mn-silicate-carbonate ore of the Kaso mine. Also at the Matsuzaka mine and the Nomine mine. Also at Koganesawa (duplication of one of previous 2 localities??).
Tokyo: Dark chocolate-brown massive stringers to 5cm with cymrite and hausmannite in banded Mn ore at the Hakumaru (Shiromaru) mine, now mostly under the waters of Okutama reservoir. Brecciated braunite masses may contain microinclusions of tokyoite.
Yamanashi: As manganese ore at the Ochiai mine with caryopilite, quartz, johannsenite, rhodochrosite and pumpellyite-(Mn).
BRITHOLITE-(Y) (ittoriumu-buriso-seki; abukuma-seki)
Fukushima: The type locality for this yttrium silicate-phosphate is Suishohyama at Iisaka in the Abukuma mountain range (from whence came the original name for this species, "abukumalite", which may indeed still deserve separate species status, as britholite-(Y) and abukumalite appear to have different space groups (Satoshi Matsubara, 2002 & 2006)). Adamantine, resinous or dull, dark reddish brown to black (yellowish brown in thin section), as rare euhedral flattened short prismatic or equant hexagonal crystals, to over 3 cm, with 12 prism faces giving an almost round cross-section with well-developed c-face and m(1010) and a(1120) prism faces, or more commonly ovoid massive aggregates to 2.5cm diameter, in feldspar associated with yttrialite, tengerite, allanite and thorogummite in pegmatite dikes in granodiorite. Also contains considerable Ca. Analysis gave (as wt% oxides): Y 46.91, Si 22.70, Ca 9.58, La-group REE 5.76, Ce-group 4.47, Mn 3.67, P 1.73, Fe''' 1.44, Fe'' 0.79, Al 0.75, Th 0.51, plus minor water, fluorine, Mg and carbonate; no U, Ti or Zr. Another specimen showed much higher phosphate - 5.84%. (Pale brown streak; H 6; D 4.35; imperfect cleavage; uneven to splintery fracture.) Also at Fusamata.
BROCHANTITE (buroshan-dohkoh)
Akita: Brochantite forms bright green, acicular crystals to 5mm long, associated with cerussite, malachite and chrysocolla in vugs in oxidized copper ore at the Kisamori mine. Bright green, transparent, small acicular xls form radial aggregates, associated with malachite and cyanotrichite in cavities in an oxidized chalcopyrite-bearing quartz vein at the Arakawa mine. Also in minor amounts at the Osarizawa mine with osarizawaite in a large limonitic oxide zone. Also at the Ani mine and the Hisaichi mine.
Shizuoka: At the Rendaiji (Kawazu) mine, lawn-like aggregates and sprays of acicular green xls to 3mm, associated with azurite, chalcocite, or carbonate-cyanotrichite, line cavities in quartz veins of an epithermal copper deposit.
BROOKITE (ita-chitan-seki)
Nagano: Golden brown transparent, thin tabular striated crystals to 2mm, with anatase and quartz crystals in limonite-filled vugs at Ikura.
Yamanashi: As rare red inclusions to 1mm in colorless quartz crystals at Takemori. Also at the Otome mine.
BRUCITE (sui-kasseki)
Aichi: Abundant as whitish crystals to 1mm at the Yoshikawa mine. Also at the Nakauri mine.
Fukuoka: Thin foliated brucite aggregates to over 13cm, pearly white or stained pale brown, associated with hydromagnesite, pyroaurite and brugnatellite, form veinlets in serpentinite at the Sanno mine and elsewhere in Sasaguri. Also at Furuyashiki and from Hamao (Same places???).
Okayama: Pearly flakes of brucite are a minor constituent of pentahydroborite veins in skarn at Fuka.
BULTFONTEINITE (barutofontin-seki)
Okayama: As aesthetic veinlet of tiny pale pink, silky needles at Fuka, with kusachiite in calcite vein at contact between limestone and gehlenite-spurrite skarn; and at the Jiro Oye outcrop here with oyelite and scawtite as thin veins in spurrite. Filiform radiating balls are rare. Also at the Mihara mine.
"BUNGONITE" (See CLINOCHLORE from Ouita-ken.)
"BUNKOLITE" (See NEOTOCITE from the Bunkou mine, Hiroshima.)
BUSERITE (byuusa-seki)
(Specimens must be kept wet because they easily dehydrate to birnessite.)
Aomori: Buserite is being microbially deposited (Gallionella ferruginea??) at the Oppu mine as low density, concentrically layered spherical nodules, from 0.5mm up to (exceptionally) 7.5cm wide (Fuji News, 8-12-2004), like brownish black "cave pearls", in waters of a plugged rhodochrosite ore gallery on the 360m level ("Lower 7 level") that was flooded for 15 years, indicating deposition rates of up to 2.5mm/yr. Smaller nodules have a shiny surface, larger ones are dull; often covered with a reddish brown gel when first found. Two analysis of metal % gave Mn 85.83, Zn 6.63, Ca 4.17, Fe 2.59, Al 0.77; and Mn 87.39, Zn 5.53, Ca 4.14, Fe 2.34, Al 0.60 (by ICP after dissolution in HCl); EDS also showed minor amounts of Na. (Genjyu Yamamoto, et al (2004) Chikyu Kagaku, 58, 375-388.)
Hokkaido: Remarkably pure, nearly ideal buserite is presently being deposited by Mn-rich hot (43 degrees C) water emanating from cracks in lava at Yuno-taki hot spring waterfall at the foot of active volcano Me-Akan, the first locality from which this mineral has been well characterized. Thin buserite platelets to 0.0004mm in aggregates to 0.001mm, associated with minor amorphous Fe hydroxide, coat waterfall rocks and PVC pipe! Can alter to takanelite or rancieite. (This much-studied mineral species has not yet been approved by the IMA-CNMMN; See refs. under type locality species list.)
Kagoshima: Microscopic flakes and filiform bundles of buserite are being currently bacterially deposited in rhythmic banding with ferrihydrite and other iron oxides in coastal hot spring waters in Nagahama port and Akayu hotsprings on Satsuma-Iou-jima. These "biomats" cement sand grains in rapidly growing "bioterraces".
BUSTAMITE (basutamu-seki)
(Japanese bustamite is found in two different types of environment: metasedimentary Mn ores, and in skarn.)
Akita: Orange-red crystals to 4mm, with galena and quartz at the Heiko mine.
Fukui: Bustamite-clinopyroxene skarns host the Zn-Pb-Ag ore in the Nakayama orebody at the Nakatatsu mine. Pale pink fibres to 5mm form compact masses, turning brownish on exposure. Often pseudomorphed by calcite or quartz. Most commonly associated with ferroan johannsenite. Analysis of quartz-contaminated material gave 14.39 wt% MnO, 11.19% CaO, 2.98% FeO. Compact rose-pink masses to several cm at the Fujii mine.
Iwate: With manganoan hedenbergite in metamorphosed bedded manganese ore at the Hijikuzu mine. With Mn oxide, carbonate and silicate minerals in Paleozoic metasedimentary ore at the Noda-Tamagawa mine, with an analysis giving the empirical formula (Ca 1.652, Mn'' 1.061, Mg 0.201, Fe'' 0.079, K 0.079, Na 0.042) (Mn'' 3.00) (Si 5.895, Al 0.046, P 0.011, Fe''' 0.002, Ti 0.002) O 18 (OH nil), which is considerably richer in Mn than most bustamites. (Also includes (wt%) BaO 0.10, carbonate(?) 0.44). (RI 1.690-1.705) Also on Sarukabe-yama in Miyako city.
Osaka: In massive metamorphic Mn silicate ore at the Hirono mine.
Saitama: As pale brownish fibres forming radial aggregates of silky luster, associated with rhodonite in contact metamorphic Cu-Pb-Zn ore at the Chichibu mine.
Shiga: At the Ishibe mine, and the Mikumo mine.
Shizuoka: Kawazu mine.
Tochigi: With tephroite in metasedimentary Paleozoic Mn ore at the Kanoiri mine.
Yamagata: With epidote, diopside, wollastonite, grossular and calcite in pyrometasomatic skarn developed in a mid-Miocene manganiferous limestone bed sandwiched between beds of propylytized pyroclastics and volcanic breccia at the Ou'hori (Ohbori) Pb-Zn-Cu mine. An analysis gave the empirical formula (Ca 2.471, Mg 0.529, Na 0.065, K 0.057) (Mn'' 2.660, Fe'' 0.168, Fe''' 0.062) (Si 5.701, Al 0.274, Ti 0.014) O [17] (OH) 0.903.
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