Bournonite (“cogwheels”) black and eye-catching “closed” twin of

and eye-catching “closed” twin of Ferberite with great form

this would make a nice addition to any thumbnail suite

There is an interesting white "vein" of Microcline running through the center of one of the Amazonite crystals

A rare and UN-repaired Tourmaline example from this beloved locality in California

which is typically what you would expect out of a metamorphic contact like this

Bournonite (“cogwheels”) black and eye-catching “closed” twin ofA hard to find "cogwheel" group of sharp, thick, blocky modified twinned crystals of Bournonite with excellent metallic luster. The piece displays well from a few angles. The stacked appearance of the crystals, combined with the bright luster, makes this one of the more eye catching smaller Bournonites available. Specimen # BOL711B23