It consists of two dozen more or less identical large chunks of rock, with one or two stand out examples. The most notable is the haematite (iron oxide) absolutely nothing like any iron ore I have ever seen (thin seams in a large chunk of base rock).
This was a lump that must have weighed about half a tonne and looked like bubbling mud, or perhaps a pile of kidneys. It had been put in a glass case, presumably to prevent it escaping. The other stand out rock was the slate. But this
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Jonathan Brind