n. a metamorphic rock consisting of interlocking grains of quartz
the GNU version of the Collaborative International Dictionary of English
n. Massive quartz occurring as a rock; a metamorphosed sandstone; -- called also quartz rock.
The Century Dictionary and Cyclopedia
n. A rock composed essentially of the mineral quartz.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. hard metamorphic rock consisting essentially of interlocking quartz crystals
Word Usage
"Richard Davis, who is applying for mining rights, says he intends to turn the canyon into a quarry, but Dr. Bart Kowallis, a professor in the Department of Geology, said the only rock to mine there is quartzite, which is extremely common in Utah."