Alamosite, (w. Anglesite, Kegelite and Melanotekite)

Chemistry: PbSiO3
Size: 45 mm
Owner: W.W. (Bill) Pinch
Photographer: John Schneider

A group of anglesite crystals (to 12mm), with a zoned coverage of spherules of blackish melanotekite, and elongated crystals of colourless to pinkish alamosite.  The alamosite crystals have well-formed, wedge-shaped terminations. Powdery-white kegelite is abundant on parts of the anglesite.  Some cores of residual galena are visible within the anglesite.


This is a very fine example of an unusual paragenesis of rare minerals.  All mineral species have been confirmed by Raman spectroscopy at the University of Arizona (RRUFF Project).  

Tsumeb is the type locality for kegelite.