Gemstones

Gemstone Categories

Explore the Gemstones We Study

Each species has its own chemistry, structure and story. These profiles summarise the properties we measure and the questions our research addresses.

Diamond

Diamond

Pure crystallised carbon formed deep in the mantle, studied for growth structure, clarity and light performance.

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Ruby

Ruby

Chromium-bearing corundum prized for saturated red colour and natural red fluorescence.

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Sapphire

Sapphire

Corundum in every colour but red, best known for blues caused by iron and titanium.

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Emerald

Emerald

Green beryl coloured by chromium and vanadium, with inclusion "gardens" that record its origin.

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Tanzanite

Tanzanite

Violet-blue zoisite from a single mining district, notable for strong pleochroism.

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Paraíba Tourmaline

Paraíba Tourmaline

Copper-bearing elbaite with vivid neon blue to green colour, studied for origin and chemistry.

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Advancing the understanding of gemstones through science, precision and innovation, from their formation deep within the Earth to the finished stone.

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Nancy Ann Rollinson, Chief Executive Officer