DALY: GEOLOGY OF THE NORTHEAST COAST OF LABRADOR. 217 



schillerizing labradorite. (Plate 11). One may collect specimens of the 

 feldspar from the numerous erratic boulders sprinkled over the hills about 

 the harbor. The direction of glacial striation shows that these must 

 have been carried to their present resting-places from the west and 

 southwest. It was likewise made clear to us on the northward journey 

 that the gabbro must be in great development in order to furnish such 

 an immense amount of erratic material as we saw. Skirting the north 

 shore of Paul's Island, the "Brave" was headed for Nam, passing 

 through a long tickle walled in on either side by high cliffs of massive 

 gabbro for fifteen miles before the mission station was reached. At 

 the station we were still about twelve miles from a quarry where 

 " precious " labradorite in place has been opened by Mr. R. G. Taber. 

 The desire to see the mineral in place decided us to risk the schooner 

 among the dangerous channels of the island-labyrinth. At Nain, how- 

 ever, we had the good fortune to find Dr. Wilfred Grenfell, superin- 

 tendent of the Deep-sea Mission, then in command of his fine new 

 steamer, the " Stratbcona." With great kindness he invited our 

 party to accompany him on the steamer to Mr. Taber's quarry ; we 

 thus spent one of the most enjoyable days of the summer in the 

 accomplishment of what would have taken the schooner, by reason of 

 the calms and baffling winds then prevailing, two or three days to 

 effect. The quarry is situated on the southwest side of a small island 

 called by the Eskimo, " Napoktulagatsuk." It lies within one fourth 

 of a mile from the mainland. 



Napoktulagatsuk is elliptical in shape and has a major axis of about 

 six hundred yards. The opening has been made in a steep glaciated 

 slope and covers an ai'ea of about twenty-five hundred square feet. At 

 the foot of the slope a thirty-foot raised beach beai's a ruined derrick, 

 and a tramway which showed by their dilapidation that work has been 

 discontinued for some years. While the whole island is composed of 

 anorthosite, the schillerizing feldspar occurs only in the form of isolated 

 patches up to fifty feet in diameter. These are generally, though not 

 always, coarser in grain than the surrounding rock, and are pegmatitic 

 in look. In the sunlight, the fresh surface of the rock presents a rich 

 and beautiful appearance. The dominant color is the familiar blue, 

 but it is associated with vivid green, bronze, orange, and red phases. 

 These pocket-like schillerizing masses are clearly contemporaneous with 

 their country-rock. Both types are characterized by the well-known 

 composition of this gabbro. Both are cut by aplitic dikes and peg- 

 matite veins. 



