This specimen is an example of a mineral that formed in a mesothermal environment.

Some hydrothermal fluids crystallize under moderate pressure and temperature conditions — between 200°C and 300°C — within Earth’s crust. Under such conditions, a mesothermal mineral-rich deposit is formed. Minerals most frequently found include enargite, bornite, tetrahedrite, tennantite, chalcocite, and other less common minerals. No single mineral is diagnostic of a mesothermal deposit.