110 



Zinc Desilverization. 



The time between No. 1 and No. 2, . - - 5 to 6 hours. 



After the second addition the lead contained silver, - - 0.87 oz. 



The third addition of zinc was - . - - . 150 lbs. 



After the third addition the lead contained silver, - - 0.09 oz. 



Number of skimmings in softeniog-furnace, . . - 3. 



The merchant lead from the softening-furnace contained silver, 0. 093 oz. 



The following tables, 1, 2 and 3, have been prepared for me by Mr. E. F. 

 Euricli, as the result of the work at the Pennsylvania Lead Company's 

 Works, in August, 1879 : — 



1. LEAD OBTAINED. 



Charged. Lbs. Lbs. 



Bunion, - - - - - -\ - 654,074 



Produced — 



Metallic dross, from refining furnace, - - 11,402 



43,540 lbs. refining furnace skimmings, at 83 per cent. 



lead, - - - - - - 35,138 



Metallic dross from the desilverizing kettle, - . 16,290 



37,357 lbs. zinc crusts, containing - - - 32,604 



27,616 lbs. softening-furnace skimmings, at 88 per cent. 



lead, - - - - - - 22,921 



Merchant lead. 



Loss, 



- 533,207 



651,562 

 2,512 



654,074 



654,074 



From the above amount of bullion, there was produced 591,244 lbs. of 

 refined bullion, ready for desilverizing. 



The silver contents of merchant lead vary from yf^ to ^-^ oz. 



The refined bullion is desilverized with from three to four zinc additions, 

 vai'ying according to the richness of the bullion. 



The total quantity of zinc added to effect the complete desilverizing of 

 591,244 lbs. refined bullion, was 7,860 lbs. 



2. SILVER OBTAINED. 



Charged — 



Silver contents of 591,244 lbs. refined bullion, 

 Produced — 

 Poured from cupelle 33,318 ozs., containing 

 Contained in 29,898 lbs. litharge, at 38.00 oz., 

 " 1,302 lbs. test bottoms, - 

 " " skimmings from filling test. 



Difference contained in dross from retorts and loss. 



Ozs. 



33,147.75 



568.06 



369.77 



61.33 



34,146.91 

 901.32 



Fine Silver. 

 Ozs. 

 35,048.23 



85,048.23 35,048.23 



