§ 191.

CUPRUM (copper), mineralized by muriatic acid and argillaceous earth. Micaceous.

Mr. Werner, in his tranſlation of Cronſtedt’s Mineralogy, part 1, page 217, has deſcribed it accurately, and kindly ſent me a ſpecimen of it, which I analyſed[[68]].

§ 192.

CUPRUM (copper), mineralized by the aerial acid. Aerated.

Cronstedt Min. §§ 194, 196. b. 3.

Mr. Fontana firſt pointed out its true compoſition. It contains about ⅔ of copper, ⅓ or ¼ of aerial acid, and a little water[[69]].

§ 193.

CUPRUM (copper), mineralized by ſulphur. Vitreous.

Cronstedt, Min. § 197. Minera cupri vitrea; a common, but improper name.