a copper arsenate mineral with formula Cu3As and hardness of 3-3.5
It has a metallic look that may turnish and cause some iridescence on surface.Can be clean with a cloth in order to restore it's original shine.
Is mixed with minor part of quartz.
It comes from Mohawk Mine, Mohawk,Keweenaw Co., Michigan USA
Size: 11.2x11.2x6.5 mm.
Weight: 7.33 ct.