One of the most classic of all Michigan copper district classics are these gemmy, bright copper-included calcite crystals. Generally, they are either dark or have poor luster but this has good luster and good translucency, with sparkling bits of copper within to give it color. A bit of leaf copper protrudes out, from inside, for added interest. Actually, these are already rare, and somewhat uncommon in thumbnail sizes (one presumes the miners were after bigger fish and did not always collect the small stuff for an as yet undeveloped market in thumbnail specimens). For what it is, very hard to find one in this quality, as a full thumbnail size. ex Robert Dunn collection, purchased by Ernie Schlichter in 1972 and then purchased by Shields Flynn upon his own mentor's passing some years ago when he took the best thumbnails of the Schlichter collection before it was sold off.