Answer | Crossword Clue |
---|---|
chalcanthite | native hydrated copper sulphate, a blue triclinic mineral usually occurring as tabular crystals |
chalcanthites | CHALCANTHITE, native hydrated copper sulphate, a blue triclinic mineral usually occurring as tabular crystals |
dioptase | A rare mineral occurring as emerald green or blue-green crystals. It consists of a hydrated silicate of copper |