While the writer was working on an unusual form of calcium carbonate usually found in caves, he collected some material closely resembling it from an adit of the disused Odin Lead Mine, Near Castleton, Derbyshire.

This material was pure white in colour, tending in places to translucency. It had a S.G. of 2.125 and a R.I. of about 1.5, though determination of the latter was rendered uncertain on account of included water. It took the from of a rippled flow covering the Carboniferous Limestone walls and roof of the passage. It was very soft, being obviously in the process of formation, though in places it had dried to form a slightly resistant encrustation.