(n.) A name originally given by the Italians to a kind of serpentine, later to the rock called euphotide, and now generally used for a coarsely crystalline, igneous rock consisting of lamellar pyroxene (diallage) and labradorite, with sometimes chrysolite (olivine gabbro).
Example Sentences:
Rhyolite
Definition:
(n.) A quartzose trachyte, an igneous rock often showing a fluidal structure.