DETERMINATION OF MINERALS. 407 



green, white. B.B. dark-colored varieties fuse easily, and give iron 

 reaction, but emerald-green var. almost infusible ; a white to yellow 

 massive garnet is hardly determinable without chemical analysis. 



VESUVIANITE (Idocrase), p. 261. H.=6*5 ; G.=3-85-3-45 ; dimetric 

 and often in prisms of four or eight sides, never fibrous ; brown to 

 pale green, ywh, bk ; B.B. fuses more easily than garnet; reaction 

 for iron. 



EFIDOTE, p. 262. H.=6-7; G. =3 25-3 -5; in moncclinie cryst. 

 and massive, rarely fibrous ; unlike amphibole in having but one 

 cleavage direction ; ywh green, bnh green, black, rdh, yellow, dark 

 gray ; B.B. fuses with intumescence. 



AMPHIBOLE, dark varieties including hornblende, actinolite, and 

 other green to gray and black kinds, p. 249. H.=56; G. =3-3 4; 

 monoclinic, in short or long prisms, often long fibrous, lamellar, and 

 massive, piisms usually four or six sides, _Z"A 1=124^°, cleavage par. 

 to 1 ; B.B. fusion easy to moderately difficult. 



ANTHOPHYLLITE, p. 252, like hornblende ; bnh gray to bnh 

 green, sometimes lustre metalloidal ; B.B. fuses with great diffi- 

 culty. 



PYROXENE, augite, and all green to bkck varieties, p. 245. 

 H. =5-6 ; G. =3 2-3 5 ; monoclinic, in short or oblong prisms, lamel- 

 lar, columnar, not often long, fibrous or asbestiform, prisms usually 

 with four or eight sides, i"Ai=87° 5', cleavage par. to 1 ; B.B. as 

 in hornblende. 



HYPERSTHENE, p. 244. H.=5-6; G.=3'39; cryst. nearly as in 

 pyroxene, but trimetric, usually foliated massive, also fibrous ; bnh 

 green, gyh black, pinchbeck-brown ; B.B. fuses with more or less 

 difficultv. Broitzite, p. 244, is similar and almost infusible. 



IOLITE, p. 264. H. =7-7-5 ; G.=26-2 7 ; blue to blue violet ; looks 

 like violet-blue glass ; B.B. fuses with much difficulty. 



Tourmaline, much Titanite, and llvaite (p. 263), B.B. give iron re- 

 action. 



C. No reaction for iron. 



SCHEELITE, p. 212. H.=45-5 ; G. =5 -9-6-1 ; ywh, gnh, rdh, pale 

 yellow ; lustre vitreous-adamantine ; fuses on the edges with great 

 difficulty. 



SCAPOLITES, p. 268. H.=5-5-6; G.=2'6 2-74; dimetric, often 

 in square prisms ; white, gray, gnh gray ; B.B. fuses easily with in- 



tllLTlGSCGIlCG 



ZOISITE. p.* 263. H =6-6"5 ; G. =3-1-34 ; trimetric, oblong prisms 

 and lamellar massive, cleavage in only one direction. 



AMPHIBOLE, white var. (tremolite), p. 249. Same as for other 

 amphibole (above), except in color ; B.B. fuses 



PYROXENE, white var., p. 215. Same as for other pyroxene (above), 

 except in color ; B.B. fuses. 



ORTHOCLASE. p. 278. H.=6 65 ; G. =2-4-2-62 ; monoclinic, stout 

 cryst., and massive, never columnar, two unequal cleavages, the 

 planes at right angles with one another, and cleavage surfaces never 

 finely striated, as seen under a pocket lens or microscope ; white, 

 gray, liesh-red, bluish, green ; B.B. fuses with some difficulty. 



