- Geology. a rock that has been crushed and sheared to such an extent that its original texture has been destroyed.
Origin of mylonite
1885–90; mylon- (representing Greek mýlos mill) + -ite1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- a fine-grained metamorphic rock, often showing banding and micaceous fracture, formed by the crushing, grinding, or rolling of the original structure
C19: from Greek mulōn mill
- A fine-grained laminated metamorphic rock in which preexisting minerals have been partially pulverized and drawn out into bands. Mylonite forms along geologic faults where shearing and grinding of rocks takes place.
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