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. […]
BROCHANTITE
BROCHANTITE Brochantite – Cu4(SO4)(OH)6 – is a fairly common sulfate, a typical secondary copper mineral. It is part of oxidized copper ores, but is not an important ore mineral. There are two monoclinic polytypes. It is soluble in acids. 1. Characteristics Crystal system: Monoclinic prismatic. Color: Various shades of green (light, dark, emerald, black). Habit: […]
BORAX
BORAX Borax – Na2[B4O5(OH)4].8H2O – is a very rare hydrated borate characteristic of evaporitic environments, mainly ephemeral salt lakes. It is the most important ore of B, an element with dozens of important applications, mainly in glass. In mining and industry, the term “borax” is used indiscriminately for various minerals that are a source of […]
BREITHAUPTITE
BREITHAUPTITE Breithauptite – NiSb – is a very rare sulfide (Dana), characteristic of hydrothermal Co-Ni-Ag veins. It is part of polymetallic ores, but is never the main ore mineral in the deposit. It is classified in the Nickeline Group. It may contain Fe, Co, As, and S. There is a variety with As. 1. Characteristics […]
BROOKITE
BROOKITE Brookite – TiO2 – is a relatively rare oxide. It is much rarer than rutile and anatase, two other polymorphs of TiO2 (other polymorphs are riesite and akaogiite). It does not form ore, but aesthetic pieces fetch high prices in the collector’s mineral trade. Brookite crystals are typically very small to microscopic, tabular in […]
BOURNONITE
BOURNONITE Bournonite – CuPbSbS3 – is a relatively common sulfosalt that always occurs in small quantities in polymetallic veins and other lead (Pb) deposits, serving as an ore of secondary importance. It is nicknamed “cog-wheel ore” because it forms cross-shaped twins at angles of nearly 90° or twins that resemble a cogwheel. These twins can […]