Star rubies and sapphires. Both these gemstones are varieties of the mineral corundum (aluminium oxide). Rubies are always a shade of red, whereas sap

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Star rubies and sapphires. Both these gemstones are varieties of the mineral corundum (aluminium oxide). Rubies are always a shade of red, whereas sapphires comes in a variety of colours.

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Photo credit: © NATURAL HISTORY MUSEUM, LONDON/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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