in mineralogy. This name has long been given indifferently to all sorts of minerals; to ores, pyrites, and to semimetals. Lately, it seems to be confined to pyrites, and Wallerius proposes to confine it to such pyrites as are regularly formed. This seems to be better than to leave it a vague and indeterminate signification, on account of the ambiguity and obscurity which might thereby be introduced. See Pyrites.