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Formula: CaCu6(AsO4)2(AsO3OH)(OH)6.3H2O
Hydrated arsenate containing hydroxyl,
mixite group
Crystal System: Hexagonal
Specific gravity: 3.49 measured, 3.50 calculated
Hardness: 2 to 3
Streak: Greenish white
Colour: Pale green, grass-green
Environments
Zálesíite is an oxidation product of chalcopyrite (Webmin). It is sometimes
associated with pharmacolite (https://www.dakotamatrix.com).
Localities
At the type locality, the Zálesí uranium deposit, Zálesí, Javorník, Jeseník District, Olomouc Region, Czech Republic, Zálesííte forms
minute, transparent, pale green acicular crystals up to 0.1 mm in length, which produce crystalline hair-like coatings up to
1 cm2 on quartz gangue,
in veinlets and filling of small cavities up to 5 mm. It originated by weathering of
chalcopyrite and cobalt
arsenides in-situ in the supergene zone.
Zálesíite was found in association with chalcopyrite,
chrysocolla, clinoclase,
conichalcite, erythrite,
malachite, metanováčekite,
metatorbernite, nováčekite,
quartz, tyrolite,
uranophane and zeunerite
(Neues Jahrbuch für Mineralogie - Abhandlungen 175.105-124).
Zálesíite from Zálesí - Image
In the Black Forest, Baden-Württemberg, Germany, mixite-group minerals mostly
consist of zálesíite with elevated bismuth or rare earth element
contents or both. It originates in baryte veins with
copper-bismuth mineralisation in
sandstone overlying
granite. The sandstones
were covered by limestone
(CM 49.5.1305–1333).
Zálesíite from Baden-Württemberg -
Image
At the Hilarion Mine, Kamariza Mines, Agios Konstantinos, Lavrion Mining District, Lavreotiki, East Attica, Attica, Greece,
agardite
forms marginal zones up to 3 μm thick of larger zoned acicular crystals 10 to 15 μm long, with a core of zálesíite
(AM 97.2064).
Zálesíite from the Hilarion Mine -
IMage
At the Taghouni Mine, Ouisselsate Caïdat, Amerzgane Cercle, Ouarzazate Province, Drâa-Tafilalet Region, Morocco, zálesíite can
form with mixite
(Minrec 38.5.402-405).
At the Aghbar Mine, Aghbar, Agdz Cercle, Zagora Province, Drâa-Tafilalet Region, Morocco, zálesíite occure as microscopic
"hedgehog" sprays of blue-green fibrous crystals, sometimes with mixite
(Minrec 38.5.402-405).
At the Mariquita Mine (Sultana Mine), Usagre, Badajoz, Extremadura, Spain, zálesíite has been identified in a
few specimens, associated with malachite,
calomel and cinnabar on
baryte. It is found as typical radial groups of pale green to apple-green
acicular crystals to 2 mm; the colour is a paler green than malachite
(MinRec 55.4.509).
Zálesíite from the Mariquita Mine -
Image
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