INDEX. 



29 r 



New England, outline of geology, 7, 8. 

 New Hampshire tin, 274. 

 New Idria, Cal., mercury, 267, 268. 

 New Jersey copper ores, 153. 



Iron mines. 123, 124. 



Limonite, 81. 



Outline of geology, 7, 8. 



Titaniferous ores, 281. 



Zinc mines, 175. 

 New Jersey Zinc and Iron Co.'s mine, 



Franklin Furnace, N. J., 176. 

 Newman Hill, Colo., banded veins, 

 35, 36. 



Figure of faulted vein at, 20. 



Lateral enrichments, 37. 



Mines of, 231. 

 New Mexico, geology, 202. 



Lead-silver mines, 181, 282. 



Silver and gold mines, 202-204. 



Triassic copper ores, 154. 

 Newton, Amador Co., Cal., copper, 



136. 



Newton Co., Mo., zinc mines, 167. 

 New York copper mine, Arizona, 150. 

 New York, iron (bo^) ore, Staten 

 Island, 74; Rye, 74. 



Iron mines of the Highlands, 123. 

 Literature, 124, 125. 



Iron ore of Adirondacks, 120, 121. 

 Literature, 122, 123. 



Lead mines, 157, 158. 



Limonite, 80, 85. 



Outline of geology, 7, 8. 



Spathic ore of Burden mines, 89. 

 at Warwarsing, 91. 



Clinton ore, 93. 



Jefferson Co., 99. 

 NeyCo.,Nev., 231. 

 Niccolite, 269. 

 Nickel and cobalt, 269-272. 

 Nickel, statistics, 271, 272. 

 Nicholas, W., cited on precipitation 



of gold, 251. 

 Nicholson, F., on the St. Genevieve, 



Mo., copper mines, 144. 

 Northampton, Mass., lead mine, 157. 

 North Carolina, gold mines, 252. 



Iron (bog) ore, 74. 



Limonite, 1, 84. 



Magnetite, 125. 

 Literature, 125. 

 Titaniferous magnetite, 281. 



Nickel, 271. 



Spathic ores, 89. 



Specular ores, 114. 



Tin, 274. 

 Nor way, nickel, 272. 



Titaniferous ores, 281. 

 Nova Scotia, Clinton iron ore, 97. 



Gold, 255. 



Nova Scotia, manganese, 266. 

 Oat Hill mercury mine, 267. 

 Ogdensburg, N. J., 174, 175-179. 

 Ohio, Clinton ore, 92, 93. 

 Limonite, 78. 

 Spathic ores, 88. 

 Okanogan Co., Wash., 238. 

 Old Dominion copper mine, Arizona, 



150. 

 Olmstead, I., cited on the Burden 



mines, New York, 90. 

 Olympic Mountains, 238. 

 Oneida Co., Idaho, 223. 

 Ontario, arsenic mine at Deloro, 260. 

 Ontario mine, Utah, 225. 

 Ontonagon, Mich , 141. 

 Ophir Canon, Utah, 194, 225. 

 Oquirrh Mountains, Utah, 192, 225. 

 Orange Co., N. Y., iron mines, 123. 

 Oregon, geology, 239. 



Mercury, 267. 

 Ore Knob, N. C., copper mines, 134, 



135. 



Ores, minerals forming, 23. 

 Original source of, 23. 

 Of iron, table of, 70. 

 Organic matter as a precipitating 



agent, 57. 

 Orton, E.. cited on dolomitization, 



22. 



Osmium, with platinum, 272. 

 Ouachita uplift of Arkansas, 170, 201, 



276. 



Ouray Co., Colo., 205. 

 Owybee Co., Idaho, 223. 

 Oxford, N. J., 123. 

 Ozark uplift, 7, 114, 170, 276. 

 Pacific slope, geology, 10. 

 Pahranagat district, Nev., 231. 

 Palmer Hill iron mines, N. Y., 122. 

 Park Co., Colo., 212. 

 Passaic iron belt, New Jersey, 124. 

 Pearce, R., bismuth with gold in 



Colorado, 250. 

 On gold ores of Gilpin Co., Colo., 



214. 



Penfield, S. F., on sperrylite, 272. 

 Peninsula copper mines, Michigan, 



141. 

 Penrose, R. A. F., on manganese, 264- 



266. 



On the iron ores of Arkansas, 279. 

 Pennsylvania, brown hematites. See 



under Iron, brown hematite. 

 Chromite, 261. 

 Clinton ore, 93. 

 Lead mines, 157. 

 Limonite, 76, 77, 81, 84, 85. 



For index of counties see un- 

 der Iron ores, limonite. 



