Ne) 
or 
flakes of ferric oxide, and small metallic haematite crystals 
may sometimes be seen in them. The sandstone above the 
arkose is dark violet-red, very fine-grained and regularly bed- 
ded. Higher up and nearer the newer igneous rocks the sand- 
stone has been discoloured. 
The sandstone on Nugarsuk and in its vicinity forms a 
belt running west to east with a breadth of half a kilometer. 
To the north this belt borders upon the newer abyssal rocks 
(granite and nordmarkite). The junction is excellently exposed 
on the rocky shore north-east of Nugarsuk: the sandstone is in 
contact with a light-gray or reddish, medium-grained arfvedso- 
nite-granite and is traversed by a network of small apophyses 
of arfvedsonite-granite, which are more coarse-grained than the 
main body of the granite. 
To the west of this locality the northern boundary of the 
sandstone belt is covered by alluvial deposits and vegetation. 
On the geological map the sandstone area borders directly on 
the nordmarkite of Kakarsuak, but in reality there seems to 
be a narrow zone of a diabase filled with sandstone fragments 
between the two rocks. 
THE ESSEXITE. 
Distribution. — The houses in Narsak are built on this 
rock, which likewise composes the low cliffs round the harbour 
and the northern part of the island outside. From here the 
essexite continues about three kilometers along the coast to 
the bay at Panernak, and it is again found at one small spot 
on the north side of the bay (see PI. IT). 
The essexite is thus exposed within quite a restricted area, 
but since it reappears at Sigsardlugtok on the east side of 
the island Tugtutok, about seven kilometers west of Narsak 
(see Pl. Il), it probably occupies a considerable area below 
the sea. At Sigsardlugtok the essexite occurs as two or three 
large dykes which continue for a distance of several kilometers 
