蓝宝石昂贵，或者是红宝石昂贵，世界什么地方产品最好呢
gem is a kind of precious stone, very good looking, I wish to buy, but not know where is available.
Your word is all right。 Gem is a kind of precious stone。 Diamond,ruby,sapphire,emerald,chrysoberyl,aquamarine,tourmaline, topaz,spinel,peridot,garnet,amethyst chrysoberyl cat's eye, and so on,are the precious gemstones。
Diamond is always transparent with colourless。 Ruby appears red and sapphire can be blue,yellow,pink,even colourless。
Now ruby in Burma and sapphire in Sri Lanka are available in the world。 In our country ruby in Yunnan and sapphire in Shandong are not too well。
The colour of ruby in Yunnan is pale red,and sapphire in Shandong is dark blue(almost black)。
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