Acanthite with Native Silver

Very good crystals of black Acanthite overgrow Native Silver from the Jáchymov mining district in the  Krušné Hory mountains of Bohemia, Czech Republic, the type locality for Acanthite.  The Native Silver covers the surface of a granular, somewhat etched matrix of tan-cream Calcite.  The Acanthite forms equant crystals of up to 3 mm diameter in clustered stacks, on and adjacent to contorted, arborescent branches of Acanthite-coated Native Silver.  Very rarely, non-coated wires of Native Silver are visible, of a dull metallic silver-white.  An impressive large thumbnail of Acanthite with Native Silver from Jáchymov.