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Vrbaite (symbol: Vrb) is an opaque to subtranslucent brittle mineral with chemical formula Tl4Hg3Sb2As8S20 and pyramidal crystals. It is names after Czech mineralogist Karel Vrba [cs]. It is bluish white with red internal reflections and dark red in translucent thin fragments. It is classified in the class "sulfides and sulfosalts".