riebeckite

 
Pronunciation: /ˈriːbɛkʌɪt/

noun

[mass noun]
  • a dark blue or black mineral of the amphibole group, occurring chiefly in alkaline igneous rocks or as blue asbestos (crocidolite).

Origin:

late 19th century: from the name of Emil Riebeck (died 1885), German explorer, + -ite1