THE LESSER METALS, CONTINUED. 269 



places, carDonates in others, with cinnabar as well as gold. The 

 following minerals have been noted : " Sulphides of arsenic, anti- 

 mony, sulphides or sulphosalts of silver, lead, copper, and zinc, ox- 

 ide, and possibly sulphide of iron; manganese, nickel and cobalt 

 compounds, and a variety of the earthy minerals " (Becker). Becker 

 thinks the source of the cinnabar is in all classes in the underlying 

 granite, and that it has come up in solution with sodium sulphide, 

 and been precipitated toward the surface by the other compounds 

 in the hot alkaline waters, with which it would remain in solution 

 at greater depths, temperatures, and pressures. The Steamboat 

 Springs are often and properly cited as metalliferous veins in ac- 

 tive process of formation. 1 



INICKEL AND COBALT. 



2.15.05. These two metals almost always occur together. 

 Their ores are the following : 



Millerite NiS, Ni. 64.4 S. 35.6. 



Niccolite NiAs, Ni. 44.0 As. 56.0. 



Linnaeite Co 3 S 4 Co. 58.0 S. 42.0. 



Also in small percentages in pyrrhotite, and a few oxidized com- 

 pounds. They may be in- pyrrhotite as the doubtful mineral 

 polydymite, a sulphide of Co, Ni, and Fe. 



2.15.06. Example 16c. (See 2.03.16 and 2.04.02.) Pyrrhotite 

 Beds or Veins. Lenticular masses of pyrrhotite interbedded in 



1 W. P. Blake, " Quicksilver Mine at Almaden, Cal.," Amer. Jour. 

 Sci., ii, XVII. 438. G. F. Becker, "Quicksilver Deposits of the Pacific 

 Slope," Monograph XIII. , U. S. Geol. Survey, Chap. 17. Rec. " On New 

 Almaden,'' Cal. Geol. Survey, I., p. 68. S. D. Christv } " On the Genesis 

 of Cinnabar Deposits," Amer. Jour. Sci., June, 187^j).'453 ; Engineering 

 and Mining Journal, Aug. 2, 1879, p. 65. D. de Cortazar, "General Re- 

 view of Occurrence, etc., of Mercury," Reps, and Awards Group I., Cen- 

 tennial Exposition, p. 196. William Irelan, Ann. Reps. Cal. State Mineral- 

 ogist. Laur, "On Steamboat Springs," Annales des Mines, 1863, 423. 

 J. Leconte and Rising, "Metalliferous Vein Formation at Sulphur Bank," 

 Amer. Jour. Sci., July, 1882 ; Engineering and Mining Journal, Aug. 26, 

 1882, p. 109. J. Leconte, "On Steamboat Springs," Amer. Jour. Sci., 

 June, 1883, p. 424. - "Genesis of Metalliferous Veins," Amer. Jour. Sci., 

 July, 1883. J. A. Phillips, "On Sulphur Bank, California," Phil. Mag., 

 1871, p. 401 ; Quar. Jour. Geol. Sci., XXXV., 1879, p. 390. Rolland, An- 

 nales des Mines, XIV., 384, 1878. B. Silliman, " Notes on the New Al- 

 maden Quicksilver Mines," Amer. Jour. Sci., ii., XXXVII. 190. Siveking, 

 B. und H. Zeitung, 1876, p. 45. 



