由铝和氧两种元素构成的刚玉，会呈现出黄色、灰色或者棕色。

Made up of the elements aluminum and oxygen, corundum also can be yellow, gray, or brown.

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由铝和氧两种元素构成的刚玉，会呈现出黄色、灰色或者棕色。

Made up of the elements aluminum and oxygen, corundum also can be yellow, gray, or brown.

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