DETERMINATION OF MINERALS. 399 
B. SULPHATES or SULPHIDES: Reaction for Sulphur 
with Soda. | 
A. FUSIBLE ; ASSAY ALKALINE AFTER FUSION. 
BARITE, p. 220. H.=2°5-3°5 ; G.=43 4°72 ; trimetric ; white, ywh, 
gyh, bluish, brown; B.B. decrepitates and fuses ; flame yellow- 
ish-green ; anhydrous. 
CELESTITE, p. 222. H.=3-35; G.=8'9-3°98 ; trimetric ; white, 
pale blue, rdh ; B.B. fuses ; flame red ; anhydrous. 
ANHYDRITE, p. 211. H.=3-85; G.=2°9-80; trimetric, with 
three rectangular and easy cleavages differing but slightly ; white, 
bluish, gyh, rdh, red; B.B. LESS flame reddish-yellow. 
GYPSUM, p. 210. H.=1:0-2; G.=2-3-2°35; monoclinic, one per- 
fect, pearly cleavage ; white, gray, but also brown, black from im- 
purities; B.B. yields much water, becomes white and crumbles 
easily. 
B. FUSIBLE ; REACTION FOR IRON. 
COPIAPITE, p. 182. H.=15; G.=2-14; yellow; on coal, becomes 
magnetic ; hydrous. 3 
Haiiynite, p. 270, also gives the sulphur reaction with soda. 
C. INFUSIBLE, OR ‘NEARLY SO. 
ALUMINITE, p. 199. H.=1-2; G.=1-66; adheres to the tongue; 
white ; B.B. blue with cobalt solution. Alunite, p. 198, is similar, 
but H.=4, and G.=2°58-2°75. 
SPHALERITH, p. 154. H.—35-4; G.=3-9-4:°2 ; isometric ; light 
to dark resin-yellow ; B.B. on coal, coating of zinc oxide. 
C. ARSENATES : Arsenical fumes on coal. 
SCORODITE, p. 185. H.—35-4; G.—3:1-33 ; trimetric ; leek-green 
to liver-brown ; B.B. fuses easily, flame blue, and with soda gives 
‘a magnetic bead ; on coal alliaceous fumes ; in HCl. sol. 
PHARMACOSIDERITE, p. 185. H.=2:5; G.=2'9-8; cubes and 
tetrahedrons ; dark green, bnh, reddish; B.B. same as for score- 
dite. 
PHARMACOLITE, p. 214. H.=2-2°5 ; G.=2°6-2°75 ; wh, gyh, rdh; 
monoclinic with one eminent cleavage; B.B. fuses, flame blue ; 
on coal, alliaceous fumes; after ignition assay alkaline; in HCl 
sol. 
