Germanite is a rare copper iron germanium sulfide mineral, Cu26Fe4Ge4S32. It was first discovered in 1922, and named for its germanium content. It is only a minor source of this important semiconductor element, which is mainly derived from the processing of the zinc sulfide mineral sphalerite. Germanite contains gallium, zinc, molybdenum, arsenic, and vanadium as impurities.
Proustite is a sulfosalt mineral consisting of silver sulfarsenide, Ag3AsS3, known also as light red silver or ruby silver ore, and an important source of the metal. It is closely allied to the corresponding sulfantimonide, pyrargyrite, from which it was distinguished by the chemical analyses of Joseph L. Proust (1754–1826) in 1804, after whom the mineral received its name.
Alunite is a hydroxylated aluminium potassium sulfate mineral, formula KAl3(SO4)2(OH)6. It was first observed in the 15th century at Tolfa, near Rome, where it was mined for the manufacture of alum. First called aluminilite by J.C. Delamétherie in 1797, this name was contracted by François Beudant three decades later to alunite.
Tephroite is the manganese endmember of the olivine group of nesosilicate minerals with the formula Mn2SiO4. A solid solution series exists between tephroite and its analogues, the group endmembers fayalite and forsterite. Divalent iron or magnesium may readily replace manganese in the olivine crystal structure.
Adamite is a zinc arsenate hydroxide mineral, Zn2AsO4OH. It is a mineral that typically occurs in the oxidized or weathered zone above zinc ore occurrences. Pure adamite is colorless, but usually it possess yellow color due to Fe compounds admixture. Tints of green also occur and are connected with copper substitutions in the mineral structure. Olivenite is a copper arsenate that is isostructural with adamite and there is considerable substitution between zinc and copper resulting in an intermediate called cuproadamite. Zincolivenite is a recently discovered mineral being an intermediate mineral with formula CuZn(AsO4)(OH). Manganese, cobalt, and nickel also substitute in the structure. An analogous zinc phosphate, tarbuttite, is known.
Bournonite is a sulfosalt mineral species, trithioantimoniate of lead and copper with the formula PbCuSbS3.
Jamesonite is a sulfosalt mineral, a lead, iron, antimony sulfide with formula Pb4FeSb6S14. With the addition of manganese it forms a series with benavidesite. It is a dark grey metallic mineral which forms acicular prismatic monoclinic crystals. It is soft with a Mohs hardness of 2.5 and has a specific gravity of 5.5 - 5.6. It is one of the few sulfide minerals to form fibrous or needle like crystals. It can also form large prismatic crystals similar to stibnite with which it can be associated. It is usually found in low to moderate temperature hydrothermal deposits.
Aerugite is a rare complex nickel arsenate mineral with a variably reported formula: Ni9(AsO4)2AsO6. It forms green to deep blue-green trigonal crystals. It has a Mohs hardness of 4 and a specific gravity of 5.85 to 5.95.
Haidingerite is a calcium arsenate mineral with formula Ca(AsO3OH)·H2O. It crystallizes in the orthorhombic crystal system as short prismatic to equant crystals. It typically occurs as scaly, botryoidal or fibrous coatings. It is soft, Mohs hardness of 2 to 2.5, and has a specific gravity of 2.95. It has refractive indices of nα = 1.590, nβ = 1.602 and nγ = 1.638.
Empressite is a mineral form of silver telluride, AgTe. It is a rare, grey, orthorhombic mineral with which can form compact masses, rarely as bipyramidal crystals.
Corderoite is an extremely rare mercury sulfide chloride mineral with formula Hg3S2Cl2. It crystallizes in the isometric crystal system. It is soft, 1.5 to 2 on the Mohs scale, and varies in color from light gray to black and rarely pink or yellow.
Temagamite is a bright white palladium mercury telluride mineral with a hardness of 2+1⁄2 on the Mohs scale. Its chemical formula is Pd3HgTe3. It was discovered at the Temagami Mine on Temagami Island, Lake Temagami in 1973, and it represents a rare mineral in the Temagami Greenstone Belt.
Baumhauerite (Pb3As4S9) is a rare lead sulfosalt mineral. It crystallizes in the triclinic system, is gray-black to blue-gray and its lustre is metallic to dull. Baumhauerite has a hardness of 3.
Pseudomalachite is a phosphate of copper with hydroxyl, named from the Greek for “false” and “malachite”, because of its similarity in appearance to the carbonate mineral malachite, Cu2(CO3)(OH)2. Both are green coloured secondary minerals found in oxidised zones of copper deposits, often associated with each other. Pseudomalachite is polymorphous with reichenbachite and ludjibaite. It was discovered in 1813. Prior to 1950 it was thought that dihydrite, lunnite, ehlite, tagilite and prasin were separate mineral species, but Berry analysed specimens labelled with these names from several museums, and found that they were in fact pseudomalachite. The old names are no longer recognised by the IMA.
Woodhouseite belongs to the beudantite group AB3(XO4)(SO4)(OH)6 where A = Ba, Ca, Pb or Sr, B = Al or Fe and X = S, As or P. Minerals in this group are isostructural with each other and also with minerals in the crandallite and alunite groups. They crystallise in the rhombohedral system with space group R3m and crystals are usually either tabular {0001} or pseudo-cubic to pseudo-cuboctahedral. Woodhouseite was named after Professor Charles Douglas Woodhouse (1888–1975), an American mineralogist and mineral collector from the University of California, Santa Barbara, US, and one-time General Manager of Champion Sillimanite, Inc.
Picropharmacolite, Ca4Mg(AsO3OH)2(AsO4)2·11H2O, is a rare arsenate mineral. It was named in 1819 from the Greek for bitter, in allusion to its magnesium content, and its chemical similarity to pharmacolite. The mineral irhtemite, Ca4Mg(AsO3OH)2(AsO4)2·4H2O, has the same composition as picropharmacolite, except that it has only four water molecules per formula unit, instead of eleven. It may be formed by the dehydration of picropharmacolite.
Fluoborite has a chemical formula of Mg3(BO3)(F,OH)3. Its name comes from its main chemical components, FLUOrine and BORon. It was first described in 1926.
Millerite is a nickel sulfide mineral, NiS. It is brassy in colour and has an acicular habit, often forming radiating masses and furry aggregates. It can be distinguished from pentlandite by crystal habit, its duller colour, and general lack of association with pyrite or pyrrhotite.
Waterhouseite, Mn7(PO4)2(OH)8, is a hydroxy manganese phosphate mineral. It is a medium-soft, brittle mineral occurring in pseudo-orthorhombic monoclinic bladed crystals and orange-brown to dark brown in color. Waterhouseite is on the softer side with a Mohs hardness of 4, has a specific gravity of 3.5 and a yellowish-brown streak. It is named after Frederick George Waterhouse, first director of the South Australian Museum, as well as recognizes the work Waterhouse Club has done in support of the South Australian Museum.
Sturmanite is a rare sulfate mineral with the chemical formula Ca6Fe3+2(SO4)2.5(B(OH)4)(OH)12 · 25 H2O. It crystallises in the tetragonal system and it has a Moh's hardness of 2.5. Sturmanite has a bright yellow to amber colour and falls in the ettringite group. It was named after Bozidar Darko Sturman (born 1937), Croatian-Canadian mineralogist and Curator Emeritus of Mineralogy, Royal Ontario Museum.
Dunn P.J., Peacor D.R., Leavens P.B., Baum J.L.,1983, American Mineralogist, Charlesite, a new mineral of the ettringite group, New Jersey [1]
