Most of the calcite I've seen from this mine has been massive habit - beautiful veins intersecting willemite. This is a crystal specimen from the same mine. Most of the crystals are colorless and translucent. Under shortwave UV the larger crystals fluoresce the typical bright orange, but the smaller crystals have a yellow/peach color. Areas of hydrozincite coat some of the crystals for a nice blue color. MW everything shifts to a more orange color and LW more yellow. Very interesting piece....
The Garpenberg mine is a currently very active zinc mine and is one of Europe's most progressive underground mining operations. Collecting is not possible, and the few specimens that reach collector's hands are highly prized. The mineralogy is quite similar to that of Franklin NJ. The mines are located in the Bergslagen mining district, a very old mining area in the southern part of Sweden. As early as 800 AD iron, silver and copper were mined. Today zinc, lead and silver ores are mined with copper and gold as by-products. The sulphide deposits at Garpenberg are distributed over 4 km, in several ore bodies found in complexly folded and faulted limestone, within an Early Proterozoic felsic volcanic succession. The stratigraphic succession is attributed to the volcanic cycle of a felsic caldera complex. The limestone hosting the ore is a stromatolitic carbonate, formed in a shallow, marine environment during a lull in volcanism. The ores formed by replacing the limestone and impregnating in veins of the volcanic rocks.