Spionkopite

spionkopite

anilite

yarrowite

djurleite

Images

Formula: Cu39S28 with oxidation states Cu1+30Cu2+9(S2)2-4S2-20 (CM 23.61-76)
Specific gravity: 5.13
Hardness: 2½ to 3
Colour: Blue
Common impurities: Fe,Zn
Environments

Hydrothermal environments

Localities

At the Type Locality, Spionkop Creek, Yarrow Creek-Spionkop Creek deposit, Alberta, Canada, spionkopite has been identified in the red-bed copper deposits. It occurs as replacement of other copper sulphides by selective removal of copper, and is also replaced by yarrowite. At the deposit copper-bearing sulphides include chalcopyrite, bornite, spionkopite, yarrowite, digenite, djurleite, idaite, wittichenite and tennantite. Near-surface leaching of copper from the natural specimens produced the following changes:
djurleite to anilite + Cu(aq) to spionkopite + Cu(aq) to yarrowite + Cu(aq) to covellite (minor) + Cu(aq) (CM 18.511-518).

At Eretria, Euboea, Central Greece, spionkopite occurs in a serpentine-hosted magnetite-chromite deposit. Associated minerals include geerite, chalcopyrite, cobaltpentlandite, magnetite, chromite, andradite, chlorite and diopside (HOM).

At Rassal, Loch Kishorn, Highland, Scotland, UK, spionkopite is always intergrown with other blue-grey as blebs, as lamellar aggregates, and as more regular lamellae in anilite .

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