mylonite

[ mahy-luh-nahyt, mil-uh- ]

noun

1. Geology. a rock that has been crushed and sheared to such an extent that its original texture has been destroyed.

mylonite

/ ˈmɪlə-; ˈmaɪləˌnaɪt /

noun

1. a fine-grained metamorphic rock, often showing banding and micaceous fracture, formed by the crushing, grinding, or rolling of the original structure

mylonite

/ mī′lə-nīt′ /

1. 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.

Word History and Origins

Origin of mylonite¹

1885–90; mylon- (representing Greek mýlos mill) + -ite ¹

Word History and Origins

Origin of mylonite¹

C19: from Greek mulōn mill

Example Sentences

In the three highest sandstone layers, the tools were all made of mylonite, a fine-grained igneous rock; the fourth layer contained tools of quartz, and among them were bones of strange animals: a giant hippopotamus, pigs 6 ft. tall, and a short-necked giraffe-like creature with antlers.

From Time Magazine Archive