Description: Millerite Ferndale 8&9 Pits, Ferndale, Rhondda, Cynon, Taff, Wales, UK Millerite, main spray 22mm. The green alteration has often been described as morenosite, but analysis at the National Museum of Wales on a number of specimens failed to find it, returning at best a mixture. Morenosite is a yet unproven in the S Wales coalfield. However, analysis of a particularly rich example from Llanbradach Colliery by my friend Prof. Pete Williams at the University of Western Sydney showed this, at least, to be nicklehehahydrite.

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