Endeavor Mine (Elura Mine), Cobar, Robinson Co., New South Wales, Australia

Ag 

Crystal System: cubic
Colour: silver-white, tarnishes dark gray to black
Lustre: metallic
Habitus: cubic, octahedral, or dodecahedral
Hardness: 2½ - 3
Fracture: none observed
Cleavage: none observed
Density: 10.497 g/cm³
Origin and geological occurrence: it is a primary hydrothermal mineral found in hydrothermal veins. Sometimes it is formed by secondary processes, especially in the oxidized portions of mineral deposits

 www.mindat.org

Smorf link

Samples:

1.1  Silver Laminar native silver in a calcite vein #sulfides