chalcocite

American  

[kal-kuh-sahyt] / ˈkæl kəˌsaɪt /

noun

1. a common mineral, cuprous sulfide, Cu 2 S: an important ore of copper.

---

chalcocite British  

/ ˈkælkəˌsaɪt /

noun

1. a lead-grey or black mineral, found as a copper ore or in veins. It is a source of copper. Composition: copper sulphide. Formula: Cu 2 S. Crystal structure: orthorhombic

---

Etymology

Origin of chalcocite

1865–70; irregular chalco- + (anthra)cite

Example Sentences

The production of copper from chalcocite is performed by roasting the Cu2S in air to produce the Cu.

From Textbooks • Feb. 14, 2019

Orvana has received approval to mine chalcocite, a mineral that is primarily copper, in a project here that the company says will create $2 billion in economic activity over 20 years.

From New York Times • May 25, 2012

Owing to the frequent presence of mechanically admixed chalcopyrite and chalcocite, the published analyses of erubescite show wide variations, the copper, for example, varying from 50 to 70%.

From Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 7 "Equation" to "Ethics" by Various

The natural inference was that as the veins were followed deeper the proportion of chalcocite would rapidly diminish, and that a leaner primary zone of chalcopyrite, enargite and other primary minerals would be met.

From The Economic Aspect of Geology by Leith, C. K. (Charles Kenneth)

Copper is known to be taken into solution as copper sulphate at the surface, and to be redeposited as chalcocite where these sulphate solutions come in contact with chalcopyrite or pyrite below.

From The Economic Aspect of Geology by Leith, C. K. (Charles Kenneth)