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



the average market value of zinc, will give $1,982,880 — the 

 value of zinc within the limits mentioned. Nature has provided 

 every local advantage that could be wished for the easy explora- 

 tion of the mines ; and embracing every expense preparatory to 

 the reduction of the ore. including its reduction also, it is pretty 

 well ascertained that the metal may be obtained in the large way 

 at a cost not exceeding three cents per pound. Here, then, there 

 would be a clear profit, deducting the cost of buildings and the 

 expenses of transportation to market, of nearly $1,000,000. If 

 we suppose the quantity of ore consumed daily to be ten tons, 

 (a small estimate,) only five years will be required to work up 

 the ore contained in the space mentioned. 



Boston, September 1, 1844. 



Mr. A. A. Hayes having, at my request, analyzed a portion of 

 a very pure specimen of the foliated red oxide of zinc, I here 

 subjoin his results, with his communication to me on the subject. 

 The original specimen weighed about three pounds, and con- 

 sisted of very brilliant horizontal layers, some of them about one 

 eighth of an inch in thickness. It affords perfect cleavage planes, 

 and the small fragments thus detached are translucent, and of a 

 deep garnet-red color. The horizontal layers are disposed upon 

 each other in a position or direction parallel with the deeply in- 

 clined walls of the bed, as if they were deposited by a gradual 

 condensation of metallic vapor rising up from the deep and in- 

 tensely heated chasm beneath. This view of its origin is sup- 

 ported by what we sometimes witness in smelting furnaces, (like 

 those for obtaining pig iron,) where the ores employed contain 

 portions of zinc. We find massive coatings of oxide of zinc lin- 

 ing the upper parts of the furnace, where the temperature be- 

 came reduced so as to admit of its condensation. Fine examples 

 of this may be seen at the furnace in West Stockbridge, Mass. ; 

 the zinc here originating from brown hematitic iron ore. Mits- 

 cherlich has recorded more remarkable instances of the produc- 

 tion of regular crystals of red oxide of zinc, identical with the 

 mineral here described. These were noticed by him in some of 

 the furnaces of Konigshutte, in Silesia. 



I would observe that Mr. Hayes's analysis has established two 

 important facts, which are contrary to the views hitherto held in 

 relation to this mineral ; first, that the deep red color is not owing 



