A137 Pietersite

Pietersite, also called "eagle's eye," was named in honor of Sid Pieters who discovered it in 1962 in Namibia, Africa. Pietersite is a trade name for a dark blue-grey breccia aggregate made up mainly of hawk's eye and tigereye. It is a variety of chalcedony (itself a variety of quartz) with embedded fibers of amphibole minerals in varying degrees of alteration. The fibers cause a blue chatoyancy like that seen in tigereye. Measures 14x10mm.