D defs.my
Entry 1 sense Webster, 1913

Covelline

/(k?-v?l"l?n)/ · Co·vel·line · IPA
01 n. A native sulphide of copper, occuring in masses of a dark blue color; -- hence called indigo copper.
  1. 1.
    A native sulphide of copper, occuring in masses of a dark blue color; -- hence called indigo copper.(Min.) Also: indigo copper