Kermesite, Antimony, Stibnite

This attractive thumbnail specimen features many radial sprays of lustrous, deep maroon kermesite crystals exhibiting a subtle semi-iridescent sheen. The kermesite is perched atop a matrix composed of metallic silver-gray stibnite and native antimony.

Kermesite, an antimony oxysulfide, typically forms as a secondary mineral through the partial oxidation of primary stibnite. This process often occurs in the presence of other antimony oxides such as valentinite or stibiconite, reflecting a complex sequence of alteration within antimony-rich environments. Associations such as this clearly illustrate mineral transformation processes. This specimen is an excellent example of secondary antimony mineralization and would make a fine addition to any collection focused on sulfides, secondary minerals, or classic Canadian localities.