Stephanite

Stephanite, a rare silver antimony sulphosalt, can develop as well-formed crystals and this stunning large thumbnail is certainly one.  Named for Archduke Stephan, we often tend to associate this species with the silver mines of Saxony, but here we have a brilliant example from Fresnillo in the state of Zacatecas in central Mexico.  A single Stephanite crystal measuring 2.1 cm across flats forms a part pseudo-hexagonal prism, displaying two complete faces and two-part faces, the remaining two are missing, this area filled with granular Stephanite forming the point of attachment when in-situ.  The double terminated crystal is steely bluish tinted silver grey, with deeply striated faces and flat pinacoid terminations.  This most elegant specimen is a wonderful example of crystallised Stephanite for the collector of rare species, aesthetics or the minerals of Mexico.