THE ISrOTSrMETALLIO MINERALS. 389 



aggregates [Rpecimon No. 67844, TT.S.N.M.]. In Arizona near Tombstone, in Yavapai 

 C'onnty, in brownisli olivo-green crystals; at tlie Mammoth (iold Mine, near Oracle, 

 Pinal County, in orange-red to l)ro\vnish red crystals with vanadinite and wulfenite. 

 A vanadinite, probably identical with descloizite, occurs at the Maytlower Mine, 

 Bald Mountain district, in Beaverhead County, Montana; it is in an impure earthy 

 form of a dull yellow to pale orange color. See further under Carnotite, p. 404. 



Vanadium is also found in small quantities in certain Swedish iron 

 ores; in the cupriferous schists of Mansfeld, Saxony; in cuprifer- 

 ous sands of Cheshire, Eng-land, and Perm, Russia; in coals from 

 various localities; in beauxite and in clay near Paris. As stated by 

 Fuchs and De Launey,^ vanadium has been shown to exist in extremely 

 small proportions in primordial rocks, from which it became concen- 

 trated in the clays on their breaking up. Certain oolitic iron ores 

 (limonites) at Mafenay, Saone et Loire, France, contain the substance 

 in such proportions that the slag* from their smelting have become 

 commercial sovirces of supply, some 60,000 kilograms of vanadic acid 

 being manufactured annually from them. 



The following referring to the occurrence and value of vanadinates 

 in the United States is of sufficient interest to bear reproduction here: 



The lead vanadates are frequently found in association with lead ores, as, for 

 instance, in the deposits at Leadville, whence some very handsome specimens were 

 formerly obtained. The most important occurrence of lead vanadates in the United 

 States, however, is probably in Arizona, where it has been reported in the ores of 

 several mines, among others those of the Castle Dome district, the Crowned King 

 mine in the Bradshaw Mountains, and the Mammoth gold mines at Mammoth, in 

 Pinal County. The last-mentioned mines are probably the only ones in the United 

 States from vs^hich vanadium minerals have been won on an industrial scale. The 

 vanadium minerals, of which nearly all the known varieties occurred, the dechenite 

 and descloizite predominating, were found in the upper levels of the mine, forming 

 about 1 per cent of the ore on the average, though within limited areas they formed 

 from 3 to 4 per cent. In the lower levels they occurred less abundantly, only an 

 occasional pocket and a small quantity of disseminated crystals being found. The 

 red crystals, according to an analysis by the late Dr. F. A. Genth, contained chlorine, 

 2.43 per cent; lead, 7.08 per cent; lead oxide, 69.98 per cent; ferric oxide, 0.48 per 

 cent; vanadic acid, 17.15 per cent; arsenic acid, 3.06 per cent, and phosphoric acid, 

 0.29 per cent. In milling the ore (gold) the vanadium minerals collected in riffles, 

 placed about 18 inches apart in the sluices. The material thus obtained was worked 

 over by hand in a sort of huddle, and the resulting concentrates were sold to the 

 Kalion Chemical Company, of Gray's Ferry Road, Philadelphia. The total quantity 

 of concentrates obtained in this manner did not exceed 6 tons. An average sample 

 of the lot, analyzed by Dr. Genth, gave the following results: Vanadic acid, 15.40 

 per cent; molybdic acid, 3.35 per cent; arsenic acid, 1.50 per cent; carbonic acid, 

 0.90 per cent; chlorine, 0.48 per cent; oxide of lead, 56.80 jier cent; oxide of zinc, 

 10.70 per cent; oxide of copper, 0.95 per cent; oxide of iron, 0.35 per cent; soluble 

 silica, 0.60 per cent; insoluble matter, 5.29 per cent. The value of the gold and 

 silver contents of the concentrates was about $140 per ton. The price realized on 

 this first lot was 12.5 cents per pound, or $250 per ton, on board the cars at Tucson. 



The vanadic salts manufactured from this lot of concentrates were said to have 



' Traits des Gites Mineraux, II, p. 95. 



