This roughly crystallized specimen of cuprian smithsonite, in crystals to 6.5 cm in length, is a pseudomorph after another mineral species, presumably after aragonite. The crystals are translucent, thin casts forming stalactite-like growths that together form the larger crystals you see. They exhibit a pleasing pastel but rich, apple-green color. A very unusual specimen! It is complete all around. I have not seen another quite like this piece.