Thesaurus Term/Concept: AMETHYST
| Identifier | 166991 |
|---|---|
| Class | OBJECT MATERIAL |
| Status | Preferred |
| Index? | Yes |
| Scope Note | A purple or violet variety of quartz often used in jewelry. Amethyst is a semi-precious stone which owes its violet colour to irridation, iron impurities, and the presence of trace elements, which result in complex crystal lattice substitutions. |