cryptoclastic

[ krip-tuh-klas-tik ]
/ ˌkrɪp təˈklæs tɪk /

adjective Geology.

(of rock) composed of minute or microscopic fragments.
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British Dictionary definitions for cryptoclastic

cryptoclastic

/ (ˌkrɪptəʊˈklæstɪk) /

adjective

(of minerals and rocks) composed of microscopic fragments

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