Note 8 — Chapter VI · PLUTONIC AND METAMORPHIC ROCKS:—CLEAVAGE AND FOLIATION.
Reading edition
Mr. Greenough (p. 78, “Critical Examination,” etc.) observes that quartz in mica-slate sometimes appears in beds and sometimes in veins. Von Buch also in his “Travels in Norway” (p. 236), remarks on alternating laminæ of quartz and hornblende-slate replacing mica-schist.