Zinc Desilveriudion . 



Ill 



3. DISTILLATION OF THE ZINC CRUSTS. 



Charged — Lbs. 



Liquated zinc crust, - - 



Produced — 

 Lead riches, ----- 31,142 



Dross from retorts, about - - . - 2,200 



Metallic zinc, about - - _ - - 2,900 



Blue powder and zinc oxide, not weighed. 



Not accounted for, ----- 1,115 



Number of charges made. 



The average weight of charge. 



Total coke consumed, 



Quantity of coke per lb., zinc crust. 



37,375 



59 



629 



21,00t) 

 0.56 



Lbs. 

 37,357 



37,375 



The following tables were taken by myself from the books at^Manstield 

 Valley, with the permission of Mr. E. F. Eurich, in June, 1880, and^ refer 

 to the montlis of April and May of that year : — 



CuPELLATiON, April 1, '80. 

 From desilverizing kettles to retorts, 

 Retorts to cupelle, - - - 



Extracted from 930 lbs. retort scrap. 

 Retort gain, . . - . 



CuPELL.'\.TiON, April, '80. 

 Charged 27,883 lbs. of lead riches, 

 Produced silver bricks shipped. 

 Silver scrap, . - - 



Litharge, 26,880 lbs., at 32 ozs.. 

 Test bottoms, 400, at 248, 

 Cupelle skimmings, 109 lbs., 

 Cupelle gain. 



CuPELLATiON, May, '80. 

 From desilverizing kettles to retorts. 

 Retorts to cupelle. 

 Extracted from retort scrap. 

 Retort gain, 



CUPELLATION, , May 8, '80. 

 40,130 lbs. lead riches, containing - 

 Silver scraps, 



Fineness samples. - . _ 



Produced silver bricks, shipped, 

 Silver scrap. 



Contained in 398 cupelle skimmings. 

 Litharge, 39,148, at 38, 

 Test bottoms, 826 lbs., at 218, - 

 Cupelle loss. 



31,790.08 

 468.81 



* 31,865.84 

 393.05 



32,258.89 



30,659,58 



723.88 



430.08 



49.60 



87.10 



32,258.89 

 31,790.08 



160.16 



31,950.24 



43,208.76 

 839.33 



31,950.24 

 43,907.69 



140.40 



44,048.09 



43,013.47 



354.35 



261.28 



743.72 



90.03 



95.89 



44,048 09 



43,208.76 



1,315.18 



34.80 



44,558.74 



44,558.74 



i 



* The weights are in ounces. 



