Definition of "schist" [schist]

• Any of various medium-grained to coarse-grained metamorphic rocks composed of laminated, often flaky parallel layers of chiefly micaceous minerals. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Through the years, the wineries have carved amazing steep terraces for grape growing along the banks of the Douro, and there is a unique soil called schist."
• "It is here, on top of a thin layer of flaky ocher-colored rock, known as schist, that the vine is at its most unexpected."
• "The flake mica produced in the U.S. comes from several sources: the metamorphic rock called schist as a by-product of processing feldspar and kaolin resources, from placer deposits, and from pegmatites."