1890.] GEOLOGISKE IAGTTAGELSEE FRA TEONDHJEMS STIFT. 59 



The little drawing p. 38 is from a granite poor in mica 

 near the church of Tydalen-, it shows in natural size cross 

 sections of sorae pecnliar inclusions, the shells of which consist 

 of biotite w hile their inside is granite like the rock outside 

 the shell. 



V. The environs of the railway station Steren. 



The drawing p. 42 is from a cutting here. The predominant 

 rock is argillaceous mica-schist. It is penetrated by a dyke of 

 fine-grained light granite which has required a thin cleavage 

 and been folded together with the surrounding rock. The figure 

 p. 43 shows the part near a in natural size. Besides this dyke 

 there are others similar; the manner in which they branch out 

 shows that they are not beds of gneiss as might be supposed at 

 the first glance. Also on the dyke in the drawing is seen a 

 small branch. 



VI. The occurrence of thulite-stone at Hinderheim. 



Thulite is, as is well known, a red mauganese zoisite. The 

 mineral is found at a place 21 km. n. of Trondhjem on the north 

 side of the Trondhjem fjord. The map p. 47 shows the locality. 

 The white is covered ground. The rock indicated by parallel 

 lines is a granitic one of middle-sized grain showing a rod- 

 structure, not very prominent however. which dips 10° to 20° 

 N.N.W. The part indicated by cross-lines is the thulite-stone. It 

 chiefly consists of a beautiful rose-red fiue-grained constituent 

 with a little quartz. The thulite-stone is used for ornamental 

 purposes on account of its uncommon and pleasing appearance. 



