103 COGGIN BROWN : MINES & MINERAL RESOURCES OF YUNNAN. 



ended it. Copper manufacture was then taken up by the Chinese 

 Government again. (Le., 373-377). 



Twelve years later, that is to say in 1910, Deprat visited the 

 Lao-tchang mines, which are situated two stages south-south-west of 

 Tung-ch'uan Fu. He found that of the four groups Sin-tchang, 

 Pe-si-la, Lao-sin-tchang and Lao-tchang, only the 1 wo latter were 

 being exploited, the others having been abandoned. The Lao- 

 tchang deposit is formed in the fissures of cracked and brccciated 

 limestone. The original pyritic mineral has been transformed into 

 carbonate as Leclere indicated, with abundant concretions of banded 

 barytes. Very numerous undergroimd workings follow the lines 

 of fracture ; some of them are 1,500 metres in length ; the lime- 

 stone massif is riddled with innumerable holes and falls are very 

 frequent. At the time of Leclcre's visit this mine found work 

 for 1,100 men. In 1910, the labour force was much the same. In 

 1898 Leclcre gave the production as 500 metric tons of crude copper 

 per annum. According to explanations given to Deprat in 1910, 

 by the officer in charge of the mine, 9G0 Chinese tons of crude copper 

 w r ere produced for the Government. This material is worth 18 

 taels per 100 kilograms. The Chinese ton is equal to 600 kilograms, 

 so that the output was 576 metric tons or slightly better than it 

 was 1 2 years earlier. The crude copper was still being refined 

 at Tung-ch'uan Fu, before shipment to Pekin. 



The first smelting is made with wood charcoal which is brought 

 from wooded regions three or four stages away by horse transport. 

 This greatly increases smelting charges. In 1910, the Government 

 paid 18 taels per 60 kilograms for crude copper. In Leclere's time 

 the price was only 12 taels for the same quantity. 



Near this pagoda, a journey of three hours from Lao-tchang, 

 Koucn-in-sa pros- carbonate of copper is found in sandstones and 

 P ccfc * quartzites. 



Four hours j ourney to the north-west of Lao-tchang there 



Sin-tien-fon" * s a wor ^^ 1 g on a thin vein in altered diabase. 



It has only yielded traces of copper carbonates. 



Lo-suy mine is one stage west of Lao-tchang at an altitude of 



Losuy 2,520 metres. Copper carbonates occur with 



phillipsite in a thin lode cutting Cambrian 



schists. There is a furnace in which crude copper is produced. 



This is refined at Tung-ch'uan Fu. The mine employs about 300 



men and produces about 60 metric tons of copper per annum. 



