PRECIOUS STONES.	247
	in the other. It practically always occurs in transparent fragments, each fragment, however, being free from flaws and of a very uniform quality. It is always derived from basic rocks. The specific gravity is 3"70 to 3'78; the hard­ness is 7-1/4. The refractive index for red light is 1-79, it never shows anomalous refraction, and it is very infusible.
	Fig. 26.—A Group of Garnet Crystals.
	The colour depends on the presence of iron and manganese, and perhaps chromium also. It is found in Bohemia in a decomposed basic rock and in detritus from this near Meronitz, Podsedlitz, and Budweis; in Saxony, at Zoblitz; in Scotland, at Elie in agglomerate ; and in South Africa in the Diamond bearing agglomerates where both a paler red and blood-red colours (Cape Ruby) occur, associated