Images
Formula: CaCu(AsO4)(OH)
Anhydrous arsenate with hydroxyl,
adelite-descloizite group,
forms a series with austinite, with
cobaltaustinite, with
duftite and with tangeite
(Mindat).
Crystal System: Orthorhombic
Specific gravity: 4.33 measured, 4.29 calculated
Hardness: 4½
Streak: Green
Colour: Green, yellow-green, greenish yellow; light green to yellowish green in transmitted light.
Solubility: Easily soluble in hydrochloric and nitric acids
Common impurities: Mg,P,V,Zn
Environments:
Conichalcite is a secondary mineral found in the
oxidised zones of copper deposits, typically an alteration product of
enargite, associated with
goethite,
austinite, olivenite,
clinoclase,
libethenite,
chenevixite, brochantite,
malachite, azurite and
jarosite
(HOM, R&M).
Localities
At Chessy-les-Mines, Auvergne-Rhône-Alpes, France, conichalcite occurs in cavities in sandstone
associated with
tyrolite
(R&M 90.6.552-556).
At Valzergues, Occitanie, France, conichalcite is associated with
quartz,
goethite, monazite-(Ce), and
agardite-(Y)
(R&M 90.6.552-556).
Conichalcite from Valzergues - Image
At the Cap Garonne Mine, Provence-Alpes-Côte d'Azur, France, conichalcite is associated with
cerussite, olivenite,
beudantite, and
mimetite
(R&M 90.6.552-556).
Conichalcite from Cap Garonne - Image
At the Clara Mine, Baden-Württemberg, Germany, conichalcite is associated with
chrysocolla and
cuprite
(R&M 90.6.552-556).
Conichalcite from the Clara Mine - Image
At the San Pietro mine, Sardinia, Italy, conichalcite is associated with calcite
(R&M 90.6.552-556).
At Bou Azzer, Drâa-Tafilalet Region, Morocco, conichalcite is associated with
roselite
and roselite-β. At the
Méchoui deposit it is associated with erythrite. At the
Ightem mine, it is
associated with malachite,
azurite,
powellite and talmessite. In the Oumlil-East open pit it
is associated with
chrysocolla, and at Ambed it occurs with
quartz. At the Aghbar open pit conichalcite commonly
encrusts
grains of
chalcopyrite and
chalcocite, and it
has also been found associated with dioptase and
chrysocolla
(R&M 90.6.552-556).
At Tsumeb, Namibia, conichalcite is most commonly associated with
adamite, but it is
also rarely associated with smithsonite,
malachite, duftite,
willemite and
olivenite
(R&M 90.6.552-556).
At the Delfina Mine, Asturias, Spain, conichalcite is associated with
azurite,
cobaltarthurite,
tyrolite or
smithsonite
(R&M 90.6.552-556).
Conichalcite from the Delfina Mine -
Image
At the Bristol mine, Lincoln County,
Nevada, USA, conichalcite is associated with jarosite,
malachite,
chrysocolla and
tenorite
(AM 11.109).
At the Tintic Mining District, Juab County, Utah, USA, conichalcite, one of the most common
copper and arsenic-bearing
minerals in the district, can be found in the Centennial Eureka, Mammoth, and Northern Spy-Carisa ore zones. It is
easily recognisable as bright green spheres to several millimeters in size and crusts usually occurring on a
quartz, baryte and sometimes
goethite matrix. It has been found infrequently as crystals, with most
crystallised specimens coming from the Centennial Eureka mine
(MinRec 55.2.196).
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