Description
Typical specimen of tennantite and löllingite crystals from the Grandes Haldes at Sainte-Marie-aux-Mines, Haut-Rhin, Alsace, in the Vosges massif. Tennantite is a sulfosalt of arsenic, copper and iron (gray copper), shown here in good black automorphic crystals on gangue. Löllingite is an iron arsenide, visible on the tennantite and on the back of the specimen as fine, shiny gray crystallizations.
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