IPA: /ˈkæl.kəˌsaɪt/
KK: /ˈkæl.kə.saɪt/
A dark gray or black mineral made of copper sulfide, which is an important source of copper.
Chalcocite is often found in copper mines as a valuable ore.
Chalcocite is formed from "chalco-" (from Greek "khalkos", meaning copper) and "-cite" (from Greek "kitos", meaning stone or rock). The word refers to a mineral that is a copper(I) sulfide, thus relating to copper in its composition.
Think of 'copper' ('chalco-') and 'stone' ('-cite') to remember that chalcocite is a mineral that contains copper.