MARBLE ISLAND. 199 



tions " quartz, enclosing chlorite and copper-pyriteS ; carbonate and 

 silicate of copper, with copper-pyrites on argillaceous slate ; ditto, 

 with a thin coating of green carbonate of copper." 



Judging from what Professor Tennant says as to a few rock- 

 specimens which were submitted to him from Repulse Bay and vicin- 

 ity, 300 miles northeastward of Mai'ble Island, the Hui'onian rocks 

 would appear to occur there also. One specimen from this bay, he 

 describes as " quartz coloured bv oxide of ii'on and containing minute 

 particles of gold." The existence of visible gold in quartz at Repulse 

 Bay is an irapoi'tant fact; It has been already mentioned that gold 

 and silver were found by assay in a specimen of iron pyrites from a 

 bay south of Cape Jones, not far south-west of Marble Island. Both 

 gold and silver have been discovered by assay in specimens of quartz 

 or pyrites which I have brought from various parts of Hudson's Bay 

 and Straits. In 1877, Dr. HaiTington, who was then chemist to the 

 • Geological Survey, detected' both gold and silver in iron pyrites which 

 I had collected fi^om a small vein cutting gneiss on a point about one 

 mile south of the mouth of Great Whale River, and also in pyrites 

 ffom veins in the dolomite which forms Dog Island, close to the main 

 shore, a few miles north' of the Cape Jones of the East-main coast. 

 The galena of the old mine, about three miles north-east of Little 

 Whale River trading post, was found to contain 5'104 ounces of 

 silver to the ton of 2,000 lbs., and that from the south side of the inlet 

 of Richmond Gulf, 12-03 ounces to the same quantity of ore. More 

 recently, Mr. Hoffillaiin, now chemist to the Survey, has found 

 small quantities of gokl and silver in quartz which I obtained from a 

 thin vein on one of the Ottawa Islands, in the north-eastern part of 

 Hudson's Bay. He has also proved the occurrence of the precious 

 metals in quartz veinstones, which I brought fi'om Cape Prince of 

 Wales, about the middle of the south side of Hudson's Straits; Cape 

 Chudleigh, on the south side of the eastern entrance to the Straits ; 

 and Nachvak Inlet, on the Labrador coast, about 140 miles south 

 of the last mentioned cape! 



From the data I have gathered at Marble Island and that afforded 

 by the valuable series of specimens which I have referred to, as well as 

 from the fact that Laurentian types of rocks are absent from the col- 

 lections, it is to be inferred, as already stated, that we have a great 

 development of the Huronian series along the 180 miles of coast fr6m 

 Chesterfield Inlet to Eskimo Point, both in regard to the variety of 



