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Pegmatites. — Pegmatitic segregations and veins occur in 
great number in the naujaite. The majority are almost horizontal, 
following the direction of the above-mentioned partings; others 
have an irregular course. The thickness may be as much as 
some few meters, but as a rule is much less; it is variable in 
one and the same vein, and most of the veins thin away and 
die out after a short time. The mineral composition is variable, 
but the pegmatites always lack the poikilitic structure, which is 
so conspicuous in the main rock. 
As an example of the pegmatite veins I may describe here 
in more detail one of the larger of them. The vein represented 
on the accompanying figure lies close above the highwater mark 
on the south side of the small island Kekertausak in Kanger- 
Fig. 3. Naujaite (A) with a pegmatitic vein (a—d). 
Island of Kekertausak, from the south. Height about 2°5 meters. 
dluarsuk. It has a certain practical interest, as considerable 
quantities of eudialyte were taken from it in 1888 for technical 
purposes. This vein is parallel with the partings of the naujaite 
(it dips about 10° towards the south); its breadth is variable, 
usually about 50—80 centimeters. It is a composite vein con- 
sisting of several parallel bands (Fig. 3, a—d). The uppermost 
of these (a) is sharply marked off from the overlying naujaite ; 
it has a breadth of 5—20 centimeters and consists of felspar 
with zinnwaldite and 2—8 centimeters long prisms of ægirine; 
it also contains some eudialyte. Under this comes a band 
0—20 centimeters thick (6), consisting of a green felt-like aggregate 
of egirine needles with a few large (10—15 centimeters long) 
prisms of the same mineral; most of these larger ægirine crystals 
3% 
