Geographic Minerals

Imogolite is an aluminum silicate clay mineral with formula: Al2SiO3(OH)4. It is an aluminum silicate clay mineral found in soils formed from volcanic ash. Its…

Ilvaite is a sorosilicate of iron and calcium with the formula: CaFe22+Fe3+Si2O7O(OH). Both manganese and magnesium substitute in the structure. It is a mineral consisting…

Ikaite is the mineral name for the hexahydrate of calcium carbonate, CaCO3·6H2O. It is a saline evaporite, consisting of hydrated calcium carbonate, found in cold…

An illite is a group of closely related non-expanding clay minerals. It is a clay mineral of a group resembling micas, with a lattice structure…

Idrialite, or idrialine, is a soft, orthorhombic hydrocarbon mineral with chemical formula: C22H14. It is a mineral probably occurring as a crystalline hydrocarbon and melting…

Icosahedrite is the first known naturally occurring quasicrystal phase. It has the composition Al63Cu24Fe13 and is a mineral approved by the International Mineralogical Association in…

Ichnusaite is a very rarely found mineral. Ichnusaite is a natural compound of thorium and molybdenum with the formula Th(MoO4)2·3H2O. It was discovered in Su…

Ianbruceite is a rare hydrated zinc arsenate with the formula [Zn2(OH)(H2O)(AsO4)](H2O)2; material from the Driggith mine has traces of cobalt. It was first discovered at…

Hyalophane or jaloallofane is a crystalline mineral, part of the feldspar group of tectosilicates. It is considered a barium-rich potassium feldspar. Its chemical formula is…

Hypersthene is a common rock-forming inosilicate mineral belonging to the group of orthorhombic pyroxenes. It is relatively common mineral and is found in igneous and…

Hyalite is a form of opal with a glassy and clear appearance which may exhibit an internal play of colors if natural inclusions are present.…

Hiddenite is a pale-to-emerald green variety of spodumene that is sometimes used as a gemstone. It is a rare, transparent variety of spodumene, colored yellow-green…