Sterling silver ring. Campitos turquoise

Sterling silver ring, campitos turquoise
Size P-Q
Turquoise is found in only a few places on earth: dry and barren regions where acidic, copper-rich groundwater seeps downward and reacts with minerals that contain phosphorus and aluminium. The result of this sedimentary process is a porous, semi-translucent to opaque compound of hydrated copper and aluminium phosphate.