In the study of optical properties of low class crystal system, the identification of optic sign has important meaning to unknown crystal and mineral determination.

在低级晶族光学特性的研究中，光性符号的确定对未知晶体及矿物的鉴定有着重要的意义。

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There are our common goal, and also a mission of our Chinese crystal craftsman — to create a world-class crystal brand!

这既是我们的共同目标，也是我们中国水晶人的共同使命——打造世界一流的水晶品牌！

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Two exhibits display Queen Mary historic artefacts, such as original silver, china and crystal, and the dining room settings from first, second and third class.

BBC: A ghostly visit on the RMS Queen Mary hotel

John Larimer, 27, a Petty Officer Third Class with the U.S. Navy, was from Crystal Lake, Ill.

WSJ: Colorado Shooting Took Mostly Young Lives

From the Caribbean to the Maldives, you can get instant access to crystal-clear waters and unbelievable views without forgoing the trappings of luxury accommodations at these five first-class overwater villas.

FORBES: Five Overwater Ocean Villas To Book Now