The box looked old, and it was turning a little yellow.

盒子显旧，有点发黄。

youdao

It was turning yellow.

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That mom who got married in 1978 and had a conservative one carat set in yellow gold is now turning it in for a three carat in platinum or white gold.

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It seems a layer of varnish added later to protect the work is in fact turning the yellow to a greyish-orange colour.

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