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what strong brown-violet, less frequently the mineral is faintly 
greenish without pleochroism. Locally it may be filled with 
extremely fine and close-lying short, black lines arranged in 
two directions in the usual manner (parallel to (100) and (001)). 
The augite grains are quite allotriomorphic and of a similar or 
somewhat larger size than the olivine. Many of them show a 
narrow green marginal zone connected with the interior by even 
transition. In the green marginal zone the extinction angle 
e:c increases to about 50°, indicating a transition to ægirine- 
augite. In several specimens of the augite-syenite the light- 
coloured augite has been replaced by a more or less strongly 
green egirine-augite with extinction angle с:а== 35° to 40°. 
The value of this angle is as usual somewhat greater in the 
central parts of the crystals than in the marginal zone. The 
egirine-augite is especially frequent in those varieties of the 
rock in which the felspar shows a tendency towards the tabular 
form. Only rarely it is observed in the same specimens of the 
rock as the light-coloured augite. 
Together with the augite one or several members of the 
hornblende-group can usually be found as subordinate consti- 
tuents. In the typical variety of the rock both green and brown 
hornblende are found, often both in parallel intergrowth with 
the augite. In sections about parallel with the plane of sym- 
metry (010) the green hornblende shows an extinction angle 
e:¢ of about 20° and the pleochroism-scheme is as follows: — 
a light yellowish green 
b dark brown-green 
c dark green 
The brown hornblende has the same extinction angle and ab- 
sorption-tints as barkevikite. In other specimens of the augite- 
syenite a brown or blue-gray catophorite-like hornblende has 
been found, with varying extinction angle, and together with it 
a few anhedra of arfvedsonite. 
