DETERMINATION OF MINERALS. 993 
BIEBERITE, p. 168. A cobalt sulphate. 
REMINGTONITE, p. 168. <A hydrous cobalt carbonate. 
3. COMPOUNDS OF MANGANESE. 
Give an amethystine globule in O.F. with borax. [The globule 
looks black if too much of the manganese mineral is used, and with 
a large excess may be opaque. ] 
1. GIVES OFF CARBONIC ACID WHEN TREATED WITH DILUTE HCl; 
LUSTRE UNMETALLIC. 
RHODOCHROSITE, p. 191. H.=35-45 ; G.=34-3°7; rose-red. 
Also manganese-bearing varieties of calcite, dolomite, ankerite, side- 
rite, all of which have the cleavage and general form of rhodochro- 
site; when containing a few per cent. of manganese they often turn 
black on exposure. 
2. TREATED WITH HCl YIELDS CHLORINE FUMES. 
MANGANITE, p. 189. H.=—4; G.=—42-4:4; in oblong trimetric 
prisms; grayish-black, streak reddish-brown ; lustre submetallic ; 
B.B. infusible ; yields water. 
PSILOMELANE, p. 189. H.=5-7; G.=8-7-4'7 ; amorphous ; black, 
streak brownish-black ; submetallic ; B.B. infusible ; yields water. 
Wad is similar, but often contains cobalt. 
PYROLUSITBSH, p. 188. H.=2-2:5; G.=4°82; in stoutish trimetric 
crystals; metallic; dark steel-gray, streak black or bluish-black ; 
_ B.B. infusible ; yields no water. 
BRAUNITE and HAUSMANNITE (p. 189) are other anhydrous 
manganese oxides. 
FRANKLINITE, p. 179. H.=5-5-65; G.=5-5:1; in octahedrons 
and massive ; iron-black, streak dark reddish brown; B.B. infusi- 
ble; but little chiorine with H Cl. 
3. CO, oR Cl NOT GIVEN OFF WHEN TREATED WITH HCl; 
ANHYDROUS. 
RHODONITE, p. 247. H.=55-6:5; G.=3-4-368; rose-red; B.B. 
fuses easily. 
TRIPLITE, p. 191. H.=55; G.=3:4-38; brown to black; B.D. 
fuses very easily, globule magnetic ; sol. in HCl. 
HELVITE, p. 256. H.=6-65; G.=31-33,; in yellowish tctrahe- 
hedrons ; B.B. fuses easily. 
SPESSARTITE (Manganesian Garnet), p. 258. H.—6:5-7; G =8°7- 
4-4; in dodecahedrons and trapezohedrons; red, brownish-red ; 
B.B. fuses easily. 
TEPHROITE, p: 256. H.=5 5-6; G.=4-412; reddish to brown 
and gray ; B.B. fuses not very easily ; gelat. in H Cl. 
Knebelite, p. 256, is related, and also gelatinizes. 
