Cuprite – Mashamba West Mine, Katanga, Dem. Rep. of Congo
Cuprite from the Democratic Republic of Congo is one of our Top 100 Minerals.
The "Shaba Crescent", as this large highly mineralized area is known, gets is name from the Swahili word for "copper". Copper from there has been known by Africans long before Europeans entered the area, the first of which were probably Portuguese merchants in search of copper and ivory in the late 15th and early 16th centuries. Henry Stanley, the American-British journalist and explorer, made several expeditions to the area in the mid-19th century. After the reports of his second journey captured the interest of Leopold II of Belgium, the king commissioned Stanley to make another, this time securing much of what is the Congo now for Belgian interests.
European mining companies greatly expanded exploration and mining operations in the late nineteenth and early twentieth centuries. The Mashamba West Mine is a relatively recent operation and was opened in early 1978. Although cuprite specimens are known from other mines in the Crescent, especially from the Likasi mine, it is the discovery of exceptional crystals in the early 1980s that brought the Congolese locality to international recognition for this mineral species.
Cuprite is not particularly rare, being the same red copper oxide as is found on some altered pennies. The mineral is a fairly common alteration product of primary copper sulfides, such as chalcopyrite and bornite, and is found in the oxidized zone of copper-bearing ore bodies. Well-developed, large crystals of cuprite are, however, quite rare in the grand scheme of things. Those of the Onganja mine in Namibia are among the largest, but they are generally coated by malachite. Some of the best specimens of recent finds at Chillagoe in Australia are probably among the finest crystals for the species, but the Mashamba matrix specimens easily rank as some the most aesthetic.
