2. A clear, hard variety of corundum used as a
gemstone that is usually blue but may be any color except red.
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一种透明的坚硬钢玉,用作宝石,通常为蓝色,但也可能是除红色以外其它任何颜色。
3. Luminiferous gem is the man made modern night shining jewel developed with modern technology by research workers and caused strong echo in
gemstone circle.
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发光宝石是近期由我国的科学工作者依靠现代科学技术研制出的“现代夜明珠”,在宝石界引起强烈反响。