Scopiform fibrous Hornblende

This brown variety should not be overlooked, especially as it is attached to a substance often called Pitchstone, figured in tab. 357 and 475, but which is rather a kind of Jasper, as it is infusible. The present specimen has some Gateau about it, others are accompanied by Iron and Copper pyrites. Blend, Quartz, &e. The radii spread from renters and occasionally intersect each other irregularly; it is not so hard as the purer kind; is more liable to decomposition, and is somewhat dull and earthy. In some specimens the fibres penetrate the Jasper, and are so intimately mixed with it, as to produce a mineral with intermediate characters. Its locality I have not exactly learnt, it is some mine In the vicinity of Redruth. Mr. Greenough possesses an excellent series of specimens, from one of which my figure is drawn. I possess a specimen marked Scotland by Mr. Day.