COBALT AND NICKEL. 163 



Obs. Occurs imbedded in granite, gneiss, mica schist sye- 

 nyte, and in granular limestone. Sometimes associated with 

 hematite, as at the Grisons. Yrieix in France, Castile, 

 Brazil, and Arendal in Norway, are some of the foreign 

 localities. 



In the United States, it occurs in crystals in Maine, at 

 "Warren ; in New Hampshire, at Lyme and Hanover ; in 

 Massachusetts, at Barre, Windsor, Snelbume, Leyden, Con- 

 way ; in Connecticut, at Monroe and Huntington ; in New 

 York, near Edenville, "Warwick, Amity, at Kingsbridge, and 

 in Essex County at Gouverneur ; in Pennsylvania, in Chester 

 County ; in the District of Columbia, at Georgetown ; in 

 North Carolina, in Buncombe County ; in Georgia, in Lin- 

 coln and Habersham counties ; at Magnet Cove in Arkansas. 



The specimens of limpid quartz, penetrated by long aci- 

 cular crystals, are often very handsome when polished. A re- 

 markable specimen of this kind was obtained in Northern 

 Vermont, and less handsome ones are not uncommon ; they 

 are found in North Carolina. Polished stones of this kind 

 are called fleches d' } amour (love's arrows) by the French. 



This ore is employed in painting on porcelain, and quite 

 largely for giving the requisite shade of color and enamel 

 appearance to artificial teeth. 



Octahedrite (Anatase) ; Brookite. These species have the same com- 

 position as rutile. Octahedrite occurs in slender nearly transparent 

 octahedrons, of a brown color. 1a1=97°51'. H. = 5'5-6. G.=3"8- 

 3*95. From Dauphiny, the Tyrol, and Brazil ; at Smithfield, R. I. 



Brookite is met with in thin hair-brown flat trimetric crystals, at- 

 tached by one edge. Also in thick iron-black crystals, as in the va- 

 riety called A rka?isite. H. =5*5-6. From Dauphiny; Snowdon in 

 Wales ; Ellenville, Ulster County, N. Y. ; Paris, Maine ; gold wash- 

 ings of North Carolina ; Magnet Cove, Arkansas (Arkansite). 



Perofskite. In cubic crystals, of yellow, brown, and black colors ; 

 chemical formula (Ti, Ca) 2 3 . From the Urals, the Tyrol, and Magnet 

 Cove, Arkansas. 



Besides the ores here described, titanium is an essential constituent 

 also of ilmenite (titanic iron), and of the silicates titanite or sphene 

 (p. 290), keilhauite (p. 291), ucarwickite ; and occurs also in the zir- 

 conia and yttria ores mchynite, atrstedite, and polymignite, and in some 

 other rare species ; sometimes in pyrochlore. 



COBALT. NICKEL. 



Cobalt has not been found native. The ores of cobalt 

 are sulphides, arsenides, arseno-sulphides, an oxide, a car- 

 bonate, a phosphate, and an arsenate ; and nickel is often 



