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latter have а light reddish colour, are comparatively small (about 
1/2 centimeter) and of varying forms giving short-rectangular 
or roundish sections. Superficially the Himausak porphyries 
have a resemblance to certain of the porphyries from Dalarne 
in Sweden, especially the so-called Klittberg porphyry, but in 
chemical and mineralogical composition they are very different 
from this; chemically they are related to the rhomb-porphyries 
of the Christiania district. 
These porphyries rest on the arfvedsonite-granite in the 
mountain Hatten; they also occur in the high mountain west 
of Hatten, and in Narsap Kaka west of the principal mass of 
llimausak; lastly, a sheet of Ilimausak porphyry has been ob- 
served at a height of about 1320 meters on the west side of 
Mount Steenstrup. 
A remarkable variety was found at a height of 1100 meters 
west of Hatten. It has phenocrysts and ground-mass like the 
ordinary llimausak porphyries, but it contains innumerable, 
small sandstone fragments. These are more or less rounded 
and vary in size from the same dimensions as the felspar 
phenocrysts down to I millimeter and less. The rock resembles 
quartz porphyry and its true nature is first seen on microscopic 
examination. 
A number of other types, as a rule of a more acid char- 
acter than those just mentioned, are found scattered about the 
whole region. Thus, in the scree under Hatten, a dark-gray, 
much decayed porphyry was found with white, rhomboidal 
phenocrysts; and pebbles of the same rock are common in the 
alluvial fan of North Siorarsuit; the rock is interesting from its 
striking resemblance to certain varieties of the Norwegian rhomb- 
porphyry. A green porphyry, which occurs as a sheet of con- 
siderable thickness on the plateau south of Tasek Lake, at a 
height of about 600 meters, has some resemblance to grorudite 
but contains no quartz. И has small, light-reddish felspar 
phenocrysts of rectangular form. — The reddish-gray syenite- 
