Precious Stones
The classic four — diamond, ruby, sapphire and emerald — plus the hardest, rarest and most valued gems.
Gemstone
Diamond
Pure crystalline carbon — the hardest natural material and the enduring symbol of the precious stones.
GemstoneEmerald
The green variety of beryl — valued for its vivid colour despite near-universal inclusions.
GemstoneRuby
The red variety of corundum — second only to diamond in hardness, and coloured by chromium.
GemstoneSapphire
Corundum in every colour but red — famed for its blue, and prized for durability.