COPPER. 107 



The ore from Lao-sin-tchang was a most entirely copper pyrites. 

 The Pe-si-la ore was mainly bornite with some covellite found in 

 veinlets in a compact state. It is a difficult ore to smelt by local 

 methods and requires a preliminary roasting. The Japanese 

 attempted to do this, but the scarcity of fuel made operations 

 impossible and the deposit is now considered unworkable. The 

 slags obtained by modern methods only contain traces of copper. 

 The ancient slags contain about 3 per cent, of copper, but those 

 found about the present smelters have been re- treated. 



The Japanese smelters contain eight furnaces. There are others 

 scattered about the district under the charge of subordinate Chinese 

 officials. The furnaces consist of brasque crucibles 1'3 metres 

 in diameter which a conical to]) 2 metres high. The blast enters 

 from a tuyer immediately opposite a door, which is filled up during 

 the fusion and only pierced by a tapping hole. The blast is produced 

 by a large cylindrical wooden blower, the piston of which is worked 

 by three gangs of four men each. The gangs relieve one another 

 frequently during a working day of twelve hours, after which they 

 are replaced by twelve fresh men. After a preliminary filling of 

 wood charcoal brought to a red heat, small quantities of the carbon- 

 ate and charcoal are constanty added and from time to time, a 

 little sulphide ore. The slags escape through a hole pierced in 

 the door, as the hearth fills with crude copper. When this appears 

 at the slag hole, the furnace is allowed to cool, after which it is 

 opened by taking down the brickwork opposite the tuyer. A 

 fusion generally lasts five days and produces about 300 kilograms 

 of crude copper. 



The total production of Tang-tan is about 500 metric tons 

 per annum. The crude copper is sent to Tung-ch'uan Fu and 

 refined there by fusion in a low blast furnace and poling with rods 

 of green wood. Part of the finished product is sent to Pekin and 

 the remainder goes to Kong-chan where there is a mint for the 

 coinage of cash. 



The Chinese officer in charge of the copper business in the Tung- 

 ch'uan Fu prefecture informed Leclere that the Japanese spent 

 a sum equal to four millions of francs in twelve years on the con- 

 struction of the smelter, the establishment of a great number of 

 roads and the exploitation of the Pe-si-la deposit. The enter- 

 prise had not become profitable when the Chinese- Japanese war 



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