Outstanding, very unusual thumbnail-size crystallized copper specimen exhibiting a combination of cubic and spinel-twin crystal forms from Michigan. The 3-dimensional “spikes” protruding from all sides of this extremely sharp copper crystal make it one of the more memorable thumbnail-size Keweenaw Peninsula copper TN’s I’ve seen in some years. The attribution of Ontonagon County is based on several expert opinions and the presence of abundant epidote and adularia in the back of the crystal. Superb!