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.
Zinkenite is a steel-gray metallic sulfosalt mineral composed of lead antimony sulfide Pb9Sb22S42. Zinkenite occurs as acicular needle-like crystals.
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.
Villiaumite is a rare halide mineral composed of sodium fluoride, NaF. It is very soluble in water and some specimens fluoresce under long and short wave ultraviolet light. It has a Mohs hardness of 2.5 and is usually red, pink, or orange in color. It is toxic to humans.
Tusionite is a rare colorless to transparent to translucent yellow brown trigonal borate mineral with chemical formula: MnSn(BO3)2. The mineral is composed of 18.86% manganese, 40.76% tin, 7.42% boron, and 32.96% oxygen. It is a late stage hydrothermal mineral and occurs rarely in granite pegmatites in miarolitic cavities.
Enargite is a copper arsenic sulfosalt mineral with formula Cu3AsS4. It takes its name from the Greek word enarge, "distinct". Enargite is a steel gray, blackish gray, to violet black mineral with metallic luster. It forms slender orthorhombic prisms as well as massive aggregates. It has a hardness of 3 and a specific gravity of 4.45.
Scorodite is a common hydrated iron arsenate mineral, with the chemical formula FeAsO4·2H2O. It is found in hydrothermal deposits and as a secondary mineral in gossans worldwide. Scorodite weathers to limonite.
Warwickite is an iron magnesium titanium borate mineral with the chemical formula (MgFe)3Ti(O, BO3)2orMg(Ti,Fe3+, Al)(BO3)O. It occurs as brown to black prismatic orthorhombic crystals which are vitreous and transparent. It has a Mohs hardness of 3 to 4 and a specific gravity of 3.36.
Cerite is a complex silicate mineral group containing cerium, formula (Ce,La,Ca)
9(Mg,Fe3+
)(SiO
4)
6(SiO
3OH)(OH)
3. The cerium and lanthanum content varies with the Ce rich species and the La rich species. Analysis of a sample from the Mountain Pass carbonatite gave 35.05% Ce
2O
3 and 30.04% La
2O
3.
Fraipontite is a zinc aluminium silicate mineral with a formula of (Zn,Al)3(Si,Al)2O5(OH)4.
Clausthalite is a lead selenide mineral, PbSe. It forms a solid solution series with galena PbS.
Thomasclarkite-(Y) is a rare mineral which was known as UK-93 until 1997, when it was renamed in honour of Thomas H. Clark (1893–1996), McGill University professor. The mineral is one of many rare-earth element minerals from Mont Saint-Hilaire. The only reported occurrence is in an alkalic pegmatite dike in an intrusive gabbro-nepheline syenite.
Brownleeite is a silicide mineral with chemical formula MnSi. It was discovered by researchers of the Johnson Space Center in Houston while analyzing the Pi Puppid particle shower of the comet 26P/Grigg-Skjellerup. The only other known natural manganese silicide is mavlyanovite, Mn5Si3.
Ancylite is a group of hydrous strontium carbonate minerals containing cerium, lanthanum and minor amounts of other rare-earth elements. The chemical formula is Sr(Ce,La)(CO3)2(OH)·H2O with ancylite-Ce enriched in cerium and ancylite-La in lanthanum.
Kaersutite is a dark brown to black double chain calcic titanium bearing amphibole mineral with formula: NaCa2(Mg3Ti4+Al)(Si6Al2)O22(O)2.
Fluellite is a mineral with the chemical formula Al2(PO4)F2(OH)•7H2O. The name is from its chemical composition, being a fluate of alumine (French).
Sweetite has a general formula of Zn(OH)2. The name is given after a curator of mineral department of The British Museum, Jessie May Sweet (1901–1979). It occurs in an oxidized vein in limestone bedrock with galena, ashoverite, wülfingite, anglesite, cerussite, hydrocerussite, litharge, fluorite, palygorskite and calcite.
Minrecordite, CaZn(CO3)2, is a very rare mineral belonging to the dolomite group, the member with Ca and Zn. It was discovered, associated with dioptase, in a specimen from the Tsumeb mine (Namibia), which is consequently its type locality. Its name is a tribute to The Mineralogical Record magazine, representing the collaboration between professional and amateur mineralogists. In this locality it is associated primarily with dioptase, and less frequently with duftite, calcite and malachite. It is a rare mineral, which has been found only in a few deposits in the world. In addition to the type locality, it appears in the Preguiça mine, in Moura, district of Beja (Portugal).
Kazakovite was named in honor of Maria Efimovna Kazakova analytical chemist. It is a type locality of Karnasurt mountain, Lovozersky District, Murmansk Oblast, Russia. It was approved by the IMA in 1974, the same year it was discovered.
