DETERMINATION OF MINERALS. 401 
B NOT FORMING A STIFF JELLY WITH ACID ; HYDROUS. 
oa 
a. Blue with cobalt solution (owing to presence of aluminum). 
WAVELLITE, p. 201. H.=38 25-4; G.=2-3-2:4; white to green, 
brown ; B.B. bluish-green flame after moistening with sulph. acid. 
LAZULITEH, p. 199. H.—5 6; G.=3 3:1; blue; B.B. green flame, 
especially after moistening with sulph. acid ; hydrous. 
TUKQUOIS, p. 200. H.=6; G.=2'6-2°85 ; sky-blue, pale green ; 
B.B. flame green. 
KAOLINITE, p. 310. H.—1-2; G.=—2-42°65 ; white when pure; 
feel greasy ; B.B. flame not green. 
GIBBSITE, p. 194. H:=2°5-3°5 ; G.=2°3-2°4; white. grayish, green- 
ish ; B.B. flame not green ; soluble in strong sulph. acid. 
DIASPORE, p. 194. H.=6°5-7; G.=8-3-3°5 ; in thin foliated crys- 
tals, plates or scvales; white, greenish, brownish; B.B. flame not 
green ; soluble in sulphuric acid after ignition. 
b. Pale red or pink color, with cobalt solution (owing to presence of 
magnesium). 
BRUCITE, p. 204. H.=25; G.—2:3-2:45; pearly, white, green- 
ish ; foliaceous or fibrous and flexible ; B.B. after ignition, alkaline. 
c. Not blue or red with cobalt solution. 
OPAL, p. 239. H.=55-65; G=1:9-2°3; B.B. with soda soluble 
with effervescence. 
GENTHITE, p. 309. H.=3-4; G.=2°4; pale green, yellowish ; 
B.B. with borax a violet bead, becoming gray in R.F. owing to 
nickel ; decomp. by H Cl. 
CHRYSOCOLLA, p. 142. H.=2-4; G.=2 2°24; pale bluish-green 
to sky-blue ; B.B. flame emerald-green, and with soda on coal globule 
of copper. 
The micas, chlorites, chloritoid, and serpentine often fuse on their 
edges with much difficulty. 
C. NOT FORMING A STIFF JELLY ; ANHYDROUS. H.=5 to 9. 
a. Blue color with cobait solution. 
CORUNDUM, p. 192. H.=9; G.=4; rhombohedral ; blue, white, 
red, gray, brown. 
CHRYSOBERYL, p. 196. H.=8'0; G.=38'7; gray, green, to eme- 
rald-green. 
TOPAZ, p. 286. H.=8; G.=3°5; in rhombic prisms with perfect 
basal cleavage, rarely columnar; white, wine-yellow, and othcr 
shades. 
RUBELLITE,, p. 283. H.=7'5 ; G.-==8; in prisms of 3, 6, or 9 sides ; 
rose-red ; reaction for boron. 
ANDALUSITE, p. 284. H.=75; G.=3:2; always in prismatic 
crystals, often tesselated within, //\ J=93° ; grayish-white to brown. 
FIBROLITE, p. 285. H.—6-7; G.=3°2; columnar or fibrous forms 
and prismatic crystals with brilliant diag. cleavage. 
