COLLECTIONS IN ECONOMIC GEOLOGY AND METALLURGY. 1 09 



The \ng copper of the region is generally free from iiijiuioiis impuri- 

 ties, especially arsenic, and has a high leputatiou at the refineries. It 

 is all shipped away to be refined, much of it being treated at works in 

 the East. 



The refining process is well illustrated by a collection from the An- 

 soiiia Brass and Copper Works, Ansouia, New Haven County, Con- 

 necticut, taken by Mr. Wm. Powe. 



Ansitnia Brass and Copper Worls. — The process of refining is essen- 

 tially the same as that described in refining the pig copper at Ste. Gene- 

 vieve. 



(I) Pig copper, from Arizona. (54344.) 



(•2) Roller scale, producod in heating and rolling copper and used in the refining 

 process to assist in the oxidation ot the impnrities of the copper. (.'i4:?4.'j. ) 



(3) Copper, taken from the hath after the lirst skimming of the slag, when tiie 

 charge becomes thoronghly melted. (54:547.) 



(A) Slag, drawn from the furnace when the charge is lirst melted. (54351.) 



(5) Copper, taken from the bath after working, dnring which the sulphur and other 

 impurities have been removed by rapid oxidation ; time of working 9 hours. (5434H.) 



(6) Slag, drawn from the furnace during the working period. (54352.) 



(7) Copper, taken from the bath after rabbling to fine copper. Rabbling removes 

 the small amount of impurities left in the copper after working, and requires from 

 1 to 2 hours. (54349.) 



(8) Slag, drawn from the furnace at the close of the oxidizing period. (5435.1.) 



(9) Copper, taken froni the bath after poling to tough copper ; time of poling 

 about 2 hours. (5'4350. ) 



(10) Slag, drawn from the furnace just after beginning to pole. (54354) 



(II) Siliceous sand, used to repair the bottom of the refining furnace. (54346.) 



(12) Pole (buttonwood poplar), used to refine the copper bath. (55403.) 



(13) Clay, used for lining ladles. Woodbridge, Middlesex County, New Jersey. 

 (5.5399.) 



(14) Bituminous coal, used in gas producers. (.55402.) 



(15) Pig copper, obtained by smelting refinery slags and other refuse in a cupola 

 furnace. (54355.1 



(16) Slag, clean slag, obtained in smelting refinery slags, etc., in the cupola. 

 Thrown away. (54398.) 



(17) Anthracite coal, used for fuel in the cupola. (.55400.) 



(18) Oyster shells, used for fiux in the cupola. (55401.) 



(19) Furnace bottom, taken from the cupola and containing metallic copper. 

 (54356.) 



Wet Process of Copper Extraction. 



Many ores contain copper in a Ibrm that can not be readily concen- 

 trated by mechanical means and arc yet too low in copper to be treated 

 directly by any of the fusion processes. To utilize such ores several wet 

 processes have been devised. 



THE HUNT AND DOUGLASS COPPER PK()("ESS. 



This i)rocess consists of treating the oxides of coi)per with a solution 

 of proto-chloride of iron and salt. By this operation the copper is con- 

 verted into subchloridc^ 1)\' the proto-cldoride of iron, and is dissolved 

 by the salt, the proto-chloride of iron being oxidized to the sesqui- 



