DETERMINATION OF MINERALS. 395 
to a magnetic globule, after roasting gives reactions for nickel, 
cobalt, and iron. 
SPHALERITE, p. 154. H.=3 5-4; G.=3-9-4:2; isometric: lustre 
submetallic ; streak te uncolored ; nearly infusible fabes and 
with borax ; on coal a coating of zine oxide. 
b. ARSENICAL FUMES, WITH OR WITHOUT SULPHUROUS. 
ARSENOPYRITE, p. 175. H.—5-6; G.—6-6°4; trimetric ; white, 
gyb, streak dark gyh black. In closed tube, red arsenic sulphide 
and metallic arsenic ; B.B. on coal fuses to magnetic globule. 
GERSDORFFITE, p. 166. H.=—5:5; G.—5-6-6'9; isometric, py- 
ritohedral; white, gyh, streak grayish-black. In closed tube 
arsenic sulphide, on coal not magnetic, and reacts for nickel and 
often cobalt. 
NICCOLITH, p. 166. H.—5-55; G.—73-7°7; hexagonal; pale 
copper-red, streak pale bnh black ; in open tube, coating of arsen- 
ous acid ; B.B. on coal no sulph. fumes, fuses to globule which re- 
acts for iron, cobalt and nickel. 
SMALTITE, p. 165. H.—5-d-6 ; G.—6°4-7:2 ; isometric ; tin-white ; 
streak gyh black ; on coal, no fumes of sulphur or only in traces. 
2. NOT YIELDING FUMES OF ANY KIND. 
STREAK UNMETALLIC. 
A. B.B. EASILY FUSIBLE, AND GIVING A MAGNETIC BEAD. 
LUSTRE SUBMETALLIC. 
ILVAITE, p. 268. H.=—5°5-6; G.—8-7-4:2 ; trimetric; gyh iron- 
black, eiecak enh or bnh black ; gelat. with H Cl. 
ALLANITE, pe2cGs,. Ho )5-6; c= 4-2; monoclinic; bnh pitch- 
black, streak gyh, bnh; B.B. fuses easily ; most varieties gelat.. 
with HCl. ‘ 
WOLFRAMITE, p, 183. H.=—5-5°5 ; G.=7:1-7°6; monoclinic ; gyh 
black or bnh black ; B.B. fuses easily, and reacts for iron, manga- 
nese, and tungsten. 
B. INFUSIBLE OR NEARLY SO. 
a. REACTION FOR IRON ; ANHYDROUS; H.=—5-6°5. 
MAGNHETITE, p. 178. G.—4°'9-5-2 ; isometric ; iron-black ; streak 
black ; strongly magnetic. 
MENACCANITE, p. 178. G.=4:5-5; rhombohedral ; iron-black : 
streak submetallic, black to bnh red ; very slightly magnetic. 
HEMATITE, p. i176. G.=—4°5-5°3; rhombohedral ; gyh iron-black, 
in very thin splinters or scales blood-red by transmitted light ; 
streak red ; sometimes slightly magnetic. 
MARTITE, p. 177. Same as hematite, but isometric. 
TANTALITE, p. 184. G.=7-8; trimetric ; iron-black, streak rdh 
brown to black. er ee ; 
