Calcite Malachite (Specimen #100284)

Mineral(s):   Malachite, Copper

Location:       Tsumeb Mine (Ongopolo Mine), Tsumeb, Oshikoto Region, Namibia                 

Size:    4.5 x 2.5 x 3.5 cm

Description:  This superb specimen features numerous primary malachite crystals of a dark green hue, with bright luster on calcite. The crystals are scattered over the white calcite creating an aesthetic specimen. The matrix is a brown copper ore and the specimen has several contact points on the back that do not detract from the specimen. The Tsumeb mine is one of the world's greatest mineral localities and has produced an astounding array of rare and beautiful minerals, many of which are found nowhere else on Earth. The Tsumeb polymetallic (Copper-Lead-Arsenic-Zinc-Silver-Germanium-Molybdenum) deposit contains one of the most diverse examples of mineralogical paragenesis observed within a single mineral deposit. The unique hydrothermal processes provided oxidizing waters to lower parts of the deposit causing the formation of a variety of minerals with increasing depth of the ore body. This provided special conditions for the development of secondary minerals of extreme beauty with respect to form and habit. On January 21, 1893, Mathew Rogers discovered the "green hill" and the site started operating in 1907 and closed in 1996 for economic reasons.  Workings include extensive underground openings to a depth of 1,000 meters.