n.
A very hard mineral composed of silica, SiO2, found worldwide in many different types of rocks, including sandstone and granite. Varieties of quartz include agate, chalcedony, chert, flint, opal, and rock crystal.
[German Quarz, from Middle High German quarc, of Slavic origin.]
quartzose quartz'ose' (kwôrt'sōs') adj.
The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.