Description: Calcite and goethite Blaengwynlais Quarry, Bwlch-y-cwm, Cardiff, Wales, UK Goethite pseudomorphing a 20mm pyrite crystal grown on a somewhat weathered calcite crystal. The goethite, clearly contemporaneous with the calcite, is loose within the cavity and can be removed and replaced. Having seen and collected numerous goethite pseudomorphs from Blaengwynlais Quarry, I have never seen a remotely similar specimen from this location.

All pictures, text, design © Forum FMF 2006-2024