出典:Wiktionary
From French schiste, from Latin schistos lapis (“the stone that is easy to split”), from Ancient Greek σχιστός (skhistós, “splittable”), from σχίζω (skhízō, “to split”).
schist (countable かつ uncountable, 複数形 schists)
出典:Wikipedia
出典:『Wikipedia』 (2011/05/25 00:12 UTC 版)
The schists constitute a group of medium-grade metamorphic rocks, chiefly notable for the preponderance of lamellar minerals such as micas, chlorite, talc, hornblende, graphite, and others. Quartz often occurs in drawn-out grains to such an extent that a particular form called quartz schist is produced. By definition, schist contains more than 50% platy and elongated minerals, often finely interleaved with quartz and feldspar. Schist is often garnetiferous.