in natural history; a name given by Dr Hill to the pyrite of a simple internal structure, and not covered with a crust.

Of these there are only two species: 1. A green variously shaped kind. 2. A botryoid kind.

The first species is the most common of all the pyrites, and appears under a great diversity of shapes. It is very hard and heavy, very readily gives fire with steel, but will not at all ferment with aquafortis. The second species is very elegant and beautiful, and its usual colour is a very agreeable pale green; but what most distinguishes it from all other pyrites is, that its surface is always beautifully elevated into tubercles of various sizes, resembling a cluster of grapes.