Peridot is 6.5 to 7 on the Mohs scale. It has fair to good toughness. Peridot is durable enough for jewelry wear but should be worn with some care so as not to scratch it or subject it to hard blows ...

This 17.53-carat amethyst displays a rich reddish purple color. - Lydia Dyer, Super Trillion Cut Amethyst gem courtesy of John Dyer & Co. Amethyst has been the most-prized quartz variety for centuries ...

Opal can range from 5 to 6.5 on the Mohs hardness scale. Hardness and toughness Gem and mineral hardness is measured on the Mohs scale. The numbers are based on the relative ease or difficulty with ...

Ruby and sapphire are varieties of the mineral corundum. - Courtesy Hamilton Jewelers Ruby is one variety of the corundum mineral species, which also includes sapphire. Ruby is highly regarded and can ...

Emerald’s lush green has soothed souls and excited imaginations since antiquity.

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珍珠生日石的意义和历史 这一迷人的六月生日石产自世界各地的海洋、湖泊和河流。这是永不过时的衣柜必备品，深受所有年龄阶段的女性热爱。珍珠的来源让我们的祖先着迷。中东地区的古人认为珍珠是从天堂滴落的眼泪。中国的传说宣称六月生日石取自龙的大脑。克里斯多弗·哥伦布（Christopher ...

The definition of padparadscha has always been debated. GIA has studied the history of the term and its modern use and indicates on a Colored Stone Identification & Origin Report when a sapphire, in ...

This jadeite "Peiyao" (Chinese Fu dog) represent mythological creatures that guard and protect celestial palaces and entrances. - Gift of Sophie Leu Jade has been cherished for thousands of years.

Diamond is the only gem made of a single element: It is typically about 99.95 percent carbon. The other 0.05 percent can include one or more trace elements, which are atoms that aren’t part of the ...

Sharon Ament, director of the Museum of London, explains the Cheapside Hoard’s unique significance. She speaks of London’s importance as a nexus of trade between the Old World and the New World, and ...

Ruby and sapphire (usually blue, but also in every other color) have been the most important colored gemstones for several thousand years. Originating historically in southeast and central Asia, and ...