Ash-coloured

We were never able to discover any fossils in the ash-coloured clay, No. 1, of the following section of the drift formation, as it presented itself high up on the Blue Earth River.

Source: wiktionary

Claude Villette, who wrote in a still earlier time, speaks of grey or ash-coloured, violet, yellow, and dove-coloured (colombin) as secondary colours to the four chief colours in use in the Gallacan Church.

Source: wiktionary

Lately, however, on looking into the question afresh, I have found proof that “russet,” although rather loosely used, did bear the meaning of grey or ash-coloured, and I now give the evidence for the benefit of others.

Source: wiktionary