This native copper crystal spinel twin are from the Central Mine in Central, Keweenaw County, Michigan, USA. This piece is double terminated and it consists of complex spinel twinned copper crystals. They are large, well defined and aesthetic. It can be displayed from all sides and angles. This piece measures 2 3/16 x 1 5/8 x 3/8 inches or 53 x 41 x 9 mm.