Part 22

CRONSTEDT Min. § 193.

It’s rarely found without ſome alloy of gold, ſilver or iron; but I have not yet fully examined it.

§ 190.

CUPRUM calciforme (copper), ſimply deprived of its phlogiſton. Calciform.

CRONSTEDT Min. § 195.

§ 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.

§ 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.

§ 193.

CUPRUM (copper), mineralized by ſulphur. Vitreous.

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

It generally contains ſome alloy of iron.

§ 194.

CUPRUM (copper), mineralized by ſulphur, and a ſmall proportion of iron.

CRONSTEDT Min. § 198, b. Minera cupri lazurea.

By a ſmall proportion of iron, I mean leſs than the weight of the copper; by a large proportion, more. This contains from 40 to 50 per cent. of copper.

§ 195.

CUPRUM (copper), mineralized by ſulphur, and a large proportion of iron. Pyritical.

CRONSTEDT Min. § 198. Pyrites Cupri.

The quantity of copper varies greatly, but ſeldom exceeds ⁴⁰⁄₁₀₀.

§ 196.

CUPRUM (copper), mineralized by ſulphur, iron and arſenic. Grey.

CRONSTEDT Min. § 198. a. Pyrites cupri griſeus.

This frequently contains an alloy of ſilver. The copper rarely exceeds ⁶⁰⁄₁₀₀.