Glossary
Species and variety
Laboratories first name the mineral species and then the variety. Ruby and sapphire are both corundum, emerald is a beryl, alexandrite a chrysoberyl, Paraíba tourmaline a tourmaline. The variety follows from colour and sometimes from special properties – for example «colour-change sapphire» for a sapphire that changes colour. Both appear in the laboratory report under «Species» and «Variety».
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Updated 2026-10-04