pwhole
Well-known member
Here's an interesting one - I think it's calcite, but in an unusual fibrous crystal form I've not seen before, and it's quite heavy - about 80mm across. It has some sort of tuff/clay attached, but also small amounts of a copper-coloured metallic mineral, which I suspect to be pyrite, but unsure - I'm no mineral expert, but I like it. Anyone have any ideas? It's from the Peak District, so reasonably confident it's not asbestos