Its unique pattern is painted with cobalt oxide on a white background and covered with transparent glaze;

其独特图案是用钴元素配制的颜料在白色瓷坯上绘出，然后挂一层透明釉。

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Glaze a building and make the glass transparent in the wintertime, opaque in the summer.

FORBES: As Clear As ...

Black ice is a glaze that forms on roads and pathways that is actually transparent, allowing the black road beneath to be seen through it.

BBC: Wiltshire black ice causes 55 road accidents