dioptases
/daɪˈɑptəsiz/
noun
- A mineral, a copper silicate hydroxide, known for its bright emerald-green color and transparent crystals.
- The museum displayed a stunning specimen of dioptases from the Congo.
- Geologists found small crystals of dioptases in the copper mine.
- Collectors prize dioptases for its vivid green hue and glassy luster.