Tangeite

vanadate

descloizite

Formula: CaCu(VO4)(OH)
Anhydrous vanadate containing hydroxyl, adelite - descloizite group, copper mineral, forms a series with conichalcite.
Specific gravity: 3.75
Hardness: 3½
Streak: Light yellow green
Colour: Yellow, yellow-green, olive green, green to dark green; light green in transmitted light.
Solubility: Soluble in acids
Environments

Sedimentary environments

Tangeite is a rare secondary supergene copper-vanadium mineral occurring in the oxidised zones of vanadium-bearing sandstone deposits (Webmin, Mindat, HOM). At Friedrichroda, Thuringia, Germany, tangeite is found with crednerite and manganese oxides (Dana).

At the Molinello mine, Italy, tangeite is associated with rhodonite, quartz, pyrobelonite, chalcocite, neotocite and copper (HOM).

At the type locality, the Tyuya-Muyun Cu-V-U deposit, Aravan District, Osh, Kyrgyzstan, tangeite occurs in sedimentary deposits (Mindat) associated with calcite, malachite and baryte (HOM).

At the the Butterley and Blaby Brick Pit, Glen Parva, Leicestershire, England, UK, tangeite has been found exposed in mudstone, surrounded by crusts of volborthite (JRS 11.54-58).

At the New Cliffe Hill quarry, Leicestershire, England, UK, tangeite is one of a suite of vanadium minerals found in supergene copper mineralisation. It occurs as masses in cavities in a ferruginous dolomite vein with calcite and baryte (JRS 11.54-58).

At the Gallagher Vanadium Property, Cochise County, Arizona, USA, tangeite has been found as small (less than 0.3 mm) crystals on iron-stained quartz and anglesite in a single specimen on the mine dump (R&M 90.4.345).

Ar Garnet Ridge, Arizona, USA, tangeite is associated with malachite, chrysocolla, tyuyamunite, chalcopyrite, pyrite and limonite (HOM).

In the sandstones of south western Colorado, USA, tangeite is found with carnotite and tyuyamunite (Dana).

At the Manganese Mine, Keweenaw County, Michigan, USA, tangeite occurs as granular to powdery patches coating fractures in calcite and manganese oxides (macfallite, orientite, braunite and hollandite) (R&M 89.6.510).

Back to Minerals