chalcedony
/kælˈsɛdəni/
noun
- A type of quartz that is usually white, gray, or blue and has a waxy shine; often used in jewelry and decorative objects.
- She wore a necklace made of polished chalcedony beads.
- Geologists found a large deposit of chalcedony in the desert.
- The ancient bowl was carved from a single piece of blue chalcedony.