68 GEOLOGY AND MINERAL EESOUKCES OF SIKHIM. 



schistose quartzite, in which very thin slightly greenish fnlige of shaly 

 matter occurs. The strike varies between NW — SE andWN W — ESE, 

 and the dip is north-eastern, about 35°. 



There are five principal galleries. The drift which vras being 

 worked at the time of my visit was found to be about 4 feet in height 

 and 3 feet in width. The roof is supported by timbering on a large 

 scale Chips of bamboo are used as lights. The gangue consists of 

 quartz and much hardened shale; soft slaty shale is the country rock. 

 The ore is extracted from the veinstone by chisel and hammer. The 

 richest ore occurs at the deeper and suddenly sloping end of this 

 drift, beloiv 40 feet ; but the miners were there in water and were 

 talking of ceasing to go any furtlier down. If the water were let 

 out — and this could be done without serious difficulty by proper con- 

 trivances — I have no doubt the ore would be found to go down much 

 deeper. Here we have to all appearance a true lode. It is about 4 

 feet in thickness and nearly vertical. 



The ore is, as usual, copper pyrites mixed with a little mundic. 

 The analysis of a sample taken at random from this deeper part 

 gave 20*31 per cent, of copper. I was informed at the mines that 

 one maund of ore yielded 20 seers of chehi (reffulus), and that 4 

 seers of chcku gave one seer of copper, so that from a maund of ore 

 there is obtained about 5 seers, or 12 per cent, copper. The copper 

 is sent from the mines in flat j^ieces. It is again refined by those who 

 work it up into vessels. Five seers of mine copper yield four on being 

 refined. 



2. Rhenoclc. — About half-way between Pachikhani and Rhenock, 

 on the south side of the Rungpo (or the Rarhichu as it is called on 

 map) and close to the bridge over it, there is exposed a fine section 

 of the Dalings in which indications of copper are found. The cupri- 

 ferous rocks in descending order are — 



Slaty shales with bands of segregated quartz in which traces 

 of copper pyrites are found. 



3" quartz with copper pyrites. ] 



1' sUity shales. | Dip ENE about 45°. 



6" quartz with copper pyrite shales. ) 



Here the ore apparently occurs in segregated veins parallel to the 

 bedding. 



3. Lingiii. — About two miles to the east of the last-named 

 locality, and a mile south of Lingui monastery at the junction of the 

 Rungpo and the Ronglichu, copjjer pyrites occur in highly quartzose 

 gneiss dipping KJ^ about 45°. The cupriferous band was found to 

 extend about 100 yards and is about 6 feet in thickness. 



