im:\'i TI KSKoi.A. M.-N. Kl. 



The amphibole has a very i'rclAc |)lio(lii-fii:-,iii IVir a liornblendo, and 

 the colours arc brown in all diicctions, bnt iaintly greenish brown on y. 

 The strongest absorption belongs to [j. The negative acute axial angle is 

 not far from 90'. The other characters are those of normal common horn- 

 blende, ß ^ 1-655 i 0-003. corresponding to lo ^/0 VeO and 15 ",0 MgO. 



The plagioclase has a noticeable inverse zonal structure. I observed 

 a section _|_ PM where the extinction angle on the border was + 35 "" and 

 in the centre but 30 . On the whole the plagioclase should contain a little 

 less than 50 per cent albite. 



Garnet-amphibolite from Taatø near Kragerø. 



The specimen investigated was collected by Professor W. C. Brøgger 

 in 1902. According to information kindly furnished by Professor J. Schete- 

 lig such rocks commonly occur as schliers or long bands in the granite 

 area of Bamle. They have some resemblance to the amphibolitic border 

 zones of the norite and hyperite-masses in the same tract, but they show no 

 apparent connection with them. 



It is a millimeter-grained hornblende-plagioclase-rock containing abundant 

 crystals of garnet, up to 2 cm in diameter. Associated wàth the garnet and 

 almost of the same size are lumps of quartz. Scales of biotite may be 

 discerned with the unaided eye in the ground-mass. 



An analysis of the garnet made by the writer resulted in the follow- 

 ina" heures: 



99-74 

 Sp.g. = 4.00 

 "d == 1-7970- 



RO : R.,0;. : SiO. = 3.40 : i : 3.72. 

 Composition Fe65Mn4Mgi5Cai^. 



The sample contained much quartz and iron ore (ilmenite). Plence the 

 deviation from the garnet ratio. 



