TUFF

Tuff

Tuff is a type of rock consisting of consolidated volcanic ash ejected from vents during a volcanic eruption. Tuff is sometimes called tufa, particularly when used as construction material, although tufa also refers to a quite different rock. Rock that contains greater than 50% tuff is considered tuffaceous.

The above text is a snippet from Wikipedia: Tuff
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tuff

Noun

  1. A light porous rock, now especially a rock composed of compacted volcanic ash varying in size from fine sand to coarse gravel.

Adjective

  1. older and simplified spelling of tough


The above text is a snippet from Wiktionary: tuff
and as such is available under the Creative Commons Attribution/Share-Alike License.

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