rock may be characterised as ‘‘sodalitite” or ‘‘sodalitgestein”!. 
On freshly broken surfaces of these varieties the above-men- 
tioned, violet-red colour is very finely displayed, but it dis- 
appears quickly under the influence of the light. The sodalite 
is everywhere perfectly fresh and more or less transparent; 
when the red colour has disappeared the mineral appears 
greenish or colourless. Some naujaite varieties of Nunasarnak 
are relatively fine-grained: while the poikilitic sodalite crystals 
in the typical rock are as a rule about half a centimeter in 
thickness, we find here varieties in which the crystals have an 
average diameter of only one millimeter. In such cases the 
dimensions of the other constituents are also reduced but not 
to such an extent; thus the felspar crystals are seldom less 
than 1°5 centimeters thick by 4 or 5 centimeters long. In com- 
parison with other rock-types, however, these varieties of nau- 
jaite may be called very coarse-grained’. 
The main interest of Nunasarnak is connected with the 
junction of the lujavrite with the sandstone and the porphyrite 
(Fig. 12, p. 73). The lujavrite is of the black, arfvedsonite 
variety, often with green veins of the ægirine variety; the flow- 
structure is exceedingly well-marked and gives the rock a pro- 
nounced schistosity or fissility. The fissility-planes become 
steeper and steeper as we approach the contact. At a distance 
of 100 meters from the latter they have a dip of 60° towards 
the south-west, and still nearer the contact they are vertical 
and parallel to the contact-plane. The endomorphic contact- 
modification has a breadth varying from 10 to 20 meters; it is 
more or less close-grained, and often of a somewhat chert-like 
appearance. At many places it is distinctly banded, parallel to 
the contact-plane; the bands are a few centimeters in breadth 
7 Meddelelser om Grønland XIV, р. 130. — H. RosexBuscn, Mikroskopische 
Physiographie II, 1 (1907), р. 240. 
2 Similar comparatively fine-grained varieties of naujaite are met with north 
of Nunarsuatsiak and in the district between Tupersuatsiak and Agpat. 
