Azurite, (w. Malachite)

Mineral: Azurite, Malachite
Chemistry: Cu3(CO3)2(OH)2
Size: 180 mm
Owner: NMNH; Smithsonian Institute
Photographer: Malcolm Southwood

A very large and aesthetic example of azurite, extensively altered to malachite; this single, terminated crystal measures 180 mm in length.  A little matrix, comprising a mixture of green copper arsenates (unidentified), is attached at the base of the crystal and on one side. Specimen number R08537, in the collection of the National Museum of Natural History, Smithsonian Institute. 


The specimen was collected from 6 Level, in the first oxidation zone. It was in the collection of Friedrich Wilhelm Kegel, director and general manager at Tsumeb between 1922 and 1932 and there is circumstantial evidence to suggest that it may have originally belonged to Tsumeb mine captain Wilhelm Klein.  A monochrome photograph of the specimen, taken by Klein and believed to date from c. 1920, is figured by Gebhard (1999, page 111).  As such it is among the earliest photographs of Tsumeb mineral specimens.


Kegel's collection was purchased by the Smithsonian in 1950 (White, 1977), while the major part of Klein's collection was bought by Harvard University in 1953.



Images courtesy of the US National Museum of Natural History, Smithsonian Institute.