BISMUTHINITE
BISMUTHINITE Bismuthinite – Bi2S3 – is a relatively common sulfide found in various distinct parageneses. It occurs within polymetallic ores and serves as an important source of Bi, though it is never the primary ore mineral in a deposit. It is classified within the Stibnite Group, with which it is isostructural and forms a solid-solution […]
BERTRANDITE
BERTRANDITE Bertrandite – Be4Si2O7(OH)2 – is a rarer (or less recognized!) sorosilicate, an alteration product of beryl found in Be-rich granitic pegmatites. It is the second most important beryllium ore, ranking only behind beryl. It may contain Fe, Ca, and Al. A vitreous, colloidal variety exists. It is pyroelectric. 1. Characteristics Crystal system: Orthorhombic pyramidal. […]
BÖHMITE
BÖHMITE Böhmite (or “bohemite”) – AlO(OH) – is a very common hydroxide, typical of residual soils. It is one of the main constituents of bauxite and thus an important Al ore. It is dimorphic with diaspore and isostructural with lepidocrocite. May contain Fe, Mn and Cr. Due to the generally submicroscopic size of its crystals, […]
BIRNESSITE
BIRNESSITE Birnessite – (Na,Ca)0.5(Mn4+,Mn3+)2O4·1.5H2O – is a common oxide, yet it is rarely conclusively identified. It occurs in Mn deposits primarily as an alteration product of other Mn minerals. It is classified within the Birnessite Group and may contain various impurities, such as Cl, Cu, Co, Fe, K, Ni, Mg, S, and Si. Due to […]
BIXBYITE
BIXBYITE Bixbyite – Mn3+2O3 – is an oxide with a fairly restricted distribution, occurring only in some very specific parageneses. It is part of some Mn ores, but is never the main ore mineral in the deposit. In the collector’s mineral market, pieces with bixbyite reach high prices due to the generally well-developed crystal shapes […]
BERTHIERITE
BERTHIERITE Berthierite – FeSb2S4 – is a relatively rare sulfide, characteristic of hydrothermal veins containing Sb minerals. It is a secondary Sb ore. Do not confuse it with “berthierin,” which is a greenish phyllosilicate (a mica) that occurs in marine sediments, lateritic soils, and polar soils. It is a member of the Berthierite Group, which […]
BABINGTONITE
BABINGTONITE Babingtonite – Ca2(Fe,Mn)FeSi5O14(OH) – is a fairly rare inosilicate. It is not important as an ore, but as a collector’s mineral it fetches quite high prices, hundreds of dollars per piece. It may contain Al, Mg, Na, and Ti. Forms epitaxies with hedenbergite and a series with manganobabingtonite. It exhibits weak magnetism. 1. Characteristics […]
BISMUTITE
BISMUTITE Bismuthite – (BiO)2CO3 – is a relatively common carbonate, typical of oxidation zones of Bi ores. It is not an important Bi ore. Its habits have no diagnostic features. Because of this, the literature on bismutite is extremely scarce, and there is little information about it. One variety, hydrobismuthite, has proven to be identical […]
BISMITE
BISMITE Bismite – Bi2O3 – is a relatively common oxide, important as a Bi ore. It is often confused with Bi carbonates and other transparent minerals formed by the alteration of Bi minerals. Due to its most common habit – earthy, powdery – there is practically no information in the literature about its microscopic characteristics. […]
BRAUNITE
BRAUNITE Braunite – Mn2+Mn3+6[O8|SiO4] -, also called braunite-1 or heteroclase, is a relatively common nesosilicate, a component of oxidized Mn mineral deposits. It is classified in the Braunite Group, forms a series with abswurmbachite, and is the Mn2+ analog of neltnerite. Braunite generally contains impurities such as Fe, Ca, B, Ba, Ti, Al, and Mg. […]