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Corundum (variety: Sapphire)

Corundum (variety: Sapphire)

The magnificent 423 carat Logan Sapphire was cut from a crystal mined in Sri Lanka and is one of the world's largest faceted blue sapphires (it is about the size of an egg). It is the heaviest mounted gem in the National Gem Collection, and in its brooch setting is framed by twenty round brilliant-cut diamonds, totaling approximately 16 carats. Sri Lanka, nicknamed the "Gem Island," has been an important source of sapphires, rubies, and other gems for more than 2,000 years.

Corundum (variety: Star Sapphire)

Corundum (variety: Star Sapphire)

Renowned for its impressive size, intense color and sharp star, the Star of Asia, which weighs 330 carats, is one of the world's finest star sapphires. Sapphires and rubies are gem varieties of the mineral corundum. The star forms when titanium atoms are trapped within the growing corundum crystal. As the crystal cools, the titanium forms needlelike crystals of the mineral rutile, which orient themselves in three directions. When properly cut, light reflecting off the three sets of needles produces the six-rayed star. The Star of Asia is from Burma and is said to have belonged to India's Maharajah of Jodhpur.


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