Cryssocola - found around gold and copper mines with hydrothermal and geothermal activity. Comes typically formed outside a quartz vein. It’s a softer material that has incredibly high copper concentrations (mostly copper oxides), which gives it its characteristic blue-green hues. The material they cut comes from Arizona, typically from mines near Tucson and Flagstaff. 

Hand-cut stone. Measures 2 1/4" x 1 3/4"