IXIOLITE
IXIOLITE IIxiolite – (Ta,Nb,Sn,Fe,Mn)4O8 , referring to members of the Ixiolite-(Mn²⁺) – Ixiolite-(Fe²⁺) Series – is a rare oxide found exclusively in granitic pegmatites, where it occurs in association with columbite and tantalite. It is a tantalum ore containing up to 69% Ta₂O₅ (in its pure form) and is a common mineral in coltan ores. […]
IODARGYRITE
IODARGYRITE Iodargyrite – AgI – is a rare halide, a typical secondary mineral of Ag deposits in arid climates. It contains 46% Ag. Sometimes the volumes of the mineral in certain occurrences make it a silver ore. Large volumes of iodargyrite have been found only in Broken Hill (Australia) and Chanarcillo (Chile). Both occurrences are […]
IRON
IRON Native iron – Fe – , also known as telluric iron, is a very rare native element due to iron’s high oxidation potential. It holds no economic importance other than as a collector’s mineral. Two types of native iron are distinguished based on carbon content. Type 1 contains 1.7–4% carbon, with native iron grains […]
IDOCRASE
IDOCRASE See “Vesuvianite”
ILVAITE
ILVAITE Ilvaite – CaFe3+Fe2+2(Si2O7)O(OH) – is a very rare sorosilicate. Macroscopically, it forms black, opaque prisms and has no economic importance. It belongs to the Lawsonite Group, is the iron analogue of manganilvaite, may contain Mg and Mn, and a monoclinic form is known. 1. Characteristics Crystal system: Orthorhombic bipyramidal. Color: Iron black, dark greenish […]
ILMENITE
ILMENITE Ilmenite – FeTiO3 – is a very common oxide that occurs in many different types of rocks. It is the most important Ti ore and the most common accessory ore mineral after magnetite. It forms 3 series, with ecandrewsite, geikelite and pyrophanite. Usually, ilmenite contains significant levels of Fe2O3 (hematite), in addition to levels […]
IDAITE
IDAITE Idaite – Cu5FeS6 – is a rarer sulfide, typically an alteration product of bornite. It integrates Cu ores based on bornite and chalcopyrite. The mineral, although accepted (“grandfathered” – described before 1959), has been poorly described, with the term referring to both impure nukundamite and a Sn-poor mawsonite-like tetragonal phase (Rice et al. 1979, […]