According to Julius Zweibel, this is one of the best of (sub) species for the lead rich variety of calcites sometimes found here, when he sold it to his friend in 1976. This piece had a slightly larger brother, which was featured on P. 66 of the MR Tsumeb issue, and was kept by Julius himself for his collection. This came at the same time. The label from Ed Ruggeiro with the piece relates their conversation and his observation which said that the Plumbian Calcite we have available here is actually the more aesthetic of the two, and looking at the sharp crystals and their superb distibution on matrix, you can believe that. The color and slight curvature of the crystals is caused by the presence of Pb. The largest of these sharp rhombs is an astounding 4.2 cm on edge, and there are six major crystals on this cabinet specimen. The Calcite cores actually have a brilliant orange fluorescence. This Plumbian Calcite is both aesthetic and important. Ex. Ed Ruggeiro Collection