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The world's foremost authority in gemology.
The world's foremost authority in gemology.

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Elongate exsolution silk (tiny rutile needles) sometimes occurs in sapphires such as this unheated stone from Sri Lanka. See more photomicrographs of natural, synthetic, and treated sapphires in the Summer issue of Gems & Gemology. http://bit.ly/2gKFkhE
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#FunFact: Sapphire belongs to the mineral species corundum and comes in a variety of colors. However, a red corundum is the only color not called sapphire; a red corundum is classified as a ruby. Which gem do you love more, sapphire or ruby? Photo: Robert Weldon/GIA
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It's the first day of autumn! Orange gemstones are a perfect addition to a fall wardrobe. Some orangey-hued gemstones to consider are sapphire, garnet, fire opal, topaz and citrine. What colors and gems make you think of fall? Photo: Robert Weldon/GIA, Dr. Edward J. Gübelin Collection
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Sapphire comes in a wide range of colors: blue, violet, green, yellow, orange, pink, purple and intermediate hues, and it can be colorless, too. Learn more about the September birthstone on our blog. http://bit.ly/2wCQF8K
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A 1.75 carat unheated ruby from Myanmar examined by Lotus Gemology in Bangkok was discovered to have a surface-reaching cavity, filled with red oil. Red oil is commonly used to improve clarity, but it also enhanced the color of the stone. Click to read more: http://bit.ly/2wVWhvi
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The GIA laboratory recently encountered a 2 carat round brilliant diamond that displayed little if any reaction to long-wave UV except for a small spot confined to the area around the culet. DiamondView imaging revealed that the diamond was cut with its growth zonation parallel to the girdle. http://bit.ly/2wViFTW
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A 3.32 carat Fancy yellow marquise diamond recently submitted to the GIA laboratory for color origin determination was of particular interest for its large, eye-visible laser manufacturing remnant (LMR), which created an internal feature shaped like a Christmas tree. What do you see? http://bit.ly/2eLoFK9
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