azurite (w. conichalcite, malachite and smithsonite)

Thick, tabular crystals of lustrous blue-black azurite (to 90 mm) on a friable and largely cryptocrystalline matrix of intergrown smithsonite and conichalcite (both XRD confirmed); the azurite crystals are partly altered to malachite close to their contact with the matrix.

This specimen is from the collection of Wilhelm Klein, a senior manager at Tsumeb between 1916 and 1939; it bears his number 1010 and his handwritten catalogue confirms that it was collected from 8 Level. It is believed to be from the pocket discovered and collected by Samuel Gordon in December 1929, the contents of which was famously divided between Gordon and the Tsumeb mine director F. W. Kegel (see Lininger 2001-2002).

conichalcite; malachite; smithsonite