﻿On the Zinc Mines of Franklin, N. J. 253 



operations were soon abandoned, and that, until within the last few 

 years, no attempts have been made to resume them, or to discover 

 any method of reducing the ore. We should except, perhaps, 

 the few attempts made at the iron works at Franklin ; but these 

 were made principally with the view of obtaining the iron from 

 the Franklinite, with which the red oxide of zinc is largely mixed. 

 They failed in both respects, and the effect was disastrous. The 

 zinc escaped in the form of white oxide, carrying off so much heat 

 as to cause the furnace to "chill up," while the but partially de- 

 oxidized iron remained in an almost immovable mass at the bot- 

 tom of the furnace. The clear-sighted Dr. Bruce, of New York, 

 was the first writer who called the attention of the public to the 

 importance of these zinc mines, and he plainly foresaw that they 

 would some day develope vast resources to the country. We are 

 also indebted to him for the earliest analysis of the ore, which 

 was soon afterwards confirmed by M. Berthier, of France.* 



As the manufacturing of pure zinc metal has become of great 

 importance, from its increased consumption in the arts and manu- 

 factures of our country, enterprising individuals have turned their 

 attention to the subject; and the discovery of extensive deposits 

 of zinc ore has been looked for with great interest. Various mines 

 have been called into notice, and some of them have been thought 

 of sufficient extent for profitable exploration ; but as they have 

 proved to yield nothing but the common sulphuret of zinc, which 

 requires a long and expensive process in its reduction, no com- 

 pany has ventured to engage in the business, and we are now 

 entirely dependent on foreign countries for our supply of this 

 metal.f At the Cornwall mines, in Great Britain, where it is 

 well known, sulphuret of zinc is found to considerable extent, 

 with calamine, or carbonate of zinc, this ore, as we are informed 

 by De la Beche, is thrown away, because it cannot be employed 

 to any profit. J Now these facts give great value to an ore which 

 is known to contain no sulphur, to the extrication of which the 



* See Bruce's Mineralogical Journal, Vol. I, p. 96, where he has described these 

 zinc ores, and given at length the modus operandi of his analysis of the red oxide. 



t Tliis now comes principally from Belgium, where the annual product is about 

 1,300 tons, and from the British isles, (mostly obtained from the carbonate,) where 

 it amounts to 2,000 tons. Russia and Poland produce about 4,000 tons annually. 



t Reports on Cornwall, Devon and West Somerset, pp. 337, 617. If it cannot 

 be profitably worked in Cornwall, where labor is so cheap, why should we expect 

 a more favorable result in this country ? 



Vol. xlviii, No. 2.— Jan.-March, 1345. 33 



