33 
The felspar erystals appear in the rock surfaces as large, 
white rectangles spotted with sodalite crystals, in form they are 
like thick plates, which a thickness of 2—6 centimeters whilst 
the length may reach 25 centimeters. The dark-coloured min- 
erals fill the angular interspaces between the light-coloured ones 
and frequently reach over 30 centimeters in breadth and length. 
The total amount of arfvedsonite and ægirine varies between a 
tenth and a fifth of the rock Their relative quantity is variable ; 
at some places one is predominant with exclusion of the other, 
and at other places both are present in considerable quantities. 
The very large size of grain of this characteristic rock 
leads one to think of a pegmatite; but there can be no talk 
of this here. Naujaite is in fact one of the main rocks in the 
whole igneous complex; from the above-mentioned coastal stretch 
at the head of Kangerdluarsuk it extends many kilometers to 
the north-west, north and north-east, forming a fairly horizontal 
igneous mass some hundreds of meters in thickness. It rests 
upon lujavrite (p. 36), and it is overlain by another related 
rock, sodalite-foyaite, which is widely distributed in the region 
of Tunugdliarfik and will be described with the latter. The 
relation of the naujaite to these rocks makes it clear, further, 
that it cannot be considered as a pegmatite formation on a 
large scale. As will be shown below, it is connected by gradual 
transition with the sodalite-foyaite, and it is distinctly older 
(i. e. earlier consolidated) than the lujavrite. 
Seen from a distance the naujaite cliffs are almost white 
or faintly bluish gray. On a freshly broken surface the rock 
usually shows a very conspicuous, violet-red colour, which 
quickly disappears in the light. This phenomenon has 
been mentioned in an earlier report." The rock is everywhere 
of a rapidly crumbling nature, but its decay is only mechanical 
! Meddelelser om Grenland XIV, 1898, р. 130. — TH. ALLAN, Memorandums 
respecting some Minerals from Greenland. Thomson's Annals of Phil. 
1813, I, p. 104. 
XXXVIII. 3 
