Nagyagite n. : A mineral of blackish lead-gray color and metallic luster, generally of a foliated massive structure; foliated tellurium. It is a telluride of lead and gold.

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Taxonomy
Nagyagite, free encyclopedia, Nagyag, Săcărâmb, Romania, gold ores, search, occurrence, dark grey, coloured, Type Locality, Sacarîmb, Hunedoara, sulfide mineral, Personal tools, minerals, Interaction, Toolbox.

Defination from the web:
Nagyagite from Nagyag (Săcărâmb), Romania. Nagyagite (Pb 5Au(Te,Sb)4S 5-8) is a rare sulfide-mineral with known occurrence associated with gold ores. Nagyagite crystals are opaque, orthorhombic and dark grey to black coloured. Type Locality is Sacarîmb (Sãcãrâmb; Nagyág), Hunedoara Co., Romania. ...