Granular Copper Pyrites

This is the second specimen I have met with of the gra-nular Copper pyrites in crystals: it is of a dull aspect, with something of the appearance of the more common Iron pyrites, which the crystallization, in cubes, having one or more of the solid angles truncated and passing to octahedrons, favours; but it is of a granular texture and otherwise differs, as it can be scraped with a knife easily, and its internal lustre is dull. The crystals rest Upon mammillated pyrites of the same kind.

From Ecton mine, which is pretty well known to produce the richly variegated Copper pyrites, coarsely shown in the present plate, but more particularly in the next.