Unpolished ruby
Yellow diamond in kimberlite
Rubies set against black rocks
Beryl emerald
A gem miner
A topaz gemstone
A star sapphire
Tourmaline gemstone
A diamond ring
Crown of Britain's Queen Mother
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Ruby in the Rough
Its green surroundings showcase a ruby from Tanzania in its unpolished beauty. Rubies, valued as precious gems, are the mineral corundum in its red form. Perhaps the country best known for its rubies was Myanmar (Burma), but the country's production has greatly decreased. Today rubies are also created synthetically in the lab.
Photograph by bildagentur-online.com/th-foto/Alamy

Gems

See pictures of gems (diamonds, rubies, and others) from National Geographic.

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