It is made of dead cells and can have a silvery-grey, white or brown appearance.

它是由死细胞构成的，有时候有一个银灰色、白色或者褐色的表面。

youdao

The Saint Lawrence, an almost constant by my side, seemed to change colour throughout the day, from choppy, muddy brown to a calm, silvery blue.

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The three grammes of copper in the 1 rupee coin (we are talking about the older style, the Jinnah on one side, Badshahi Masjid on the other, a brown colour, not the newer silvery looking coin) therefore has a refined value of 2.64 US cents.

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