graywacke
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English
Definitions
noun
- A hard dark sandstone with poorly sorted angular grains of quartz, feldspar, and small rock fragments in a compact, clay-fine matrix.
Related words
Synonyms
feldspathicgreywackegreywackesargilliteamphibolitepumiceousgreisendolostonewackehornfelswackestonephylliteglauconiticargillitesinterbeddedtuffaceous