CUPRUM,
OR
COPPER.
Its ſpecific gravity is 8,876. Nitrous acid diſſolve it readily, muriatic acid ſlowly, and the vitriolic requires intenſe boiling. The phlogiſton, ſeparated in the ſolution of 100 parts, may be expreſſed by 312. The weakeſt vegetable acids act upon it, eſpecially after calcination, and ſo do alkalies, the volatile alkaly eſpecially. With reſpect to the power with which it retains the phlogiſton, copper holds the eighth place. It melts with 1450 degrees of heat.
CUPRUM nativum (copper native). Native.
Cronstedt Min. § 193.
It’s rarely found without ſome alloy of gold, ſilver or iron; but I have not yet fully examined it.
CUPRUM calciforme (copper), ſimply deprived of its phlogiſton. Calciform.
Cronstedt Min. § 195.
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].
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].
CUPRUM (copper), mineralized by ſulphur. Vitreous.
Cronstedt, Min. § 197. Minera cupri vitrea; a common, but improper name.
It generally contains ſome alloy of iron.
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.
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.
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.