Fig. 10. Levynite; Henry Glacier. 



127 



They are striated parallel to their intersections with the faces 

 of this zone. Moreover since the zone cv --= {OOOI, 2.10.12.7} 

 contains the face // {2 . 10.12. 11 }, tiie two scalenohedra и and v 

 lying in this and in similar zones meet in horizontal edges. 



A penetration-twin with the above-mentioned scalenohedral 

 faces is represented in fig. 10. The twin formation is however, 

 not always equally per- 

 fect, so that sometimes 

 the larger part of the 

 crystal may belong to 

 a single individual 

 The thinner crystals 

 are partly developed 

 in the same way, but here the forms /{lOTl} and s{022l} are 

 generally more prominent; the exact relations are not easily 

 made out owing to the very narrow faces. 



G aase fjord. On the south side a single fragment of a 

 light grey dolerite rock was found. This is labelled «main 

 rock» and contains several cavities with small levynite crystals 

 from 1 — 3™™ in length. Small stilbite crystals are also present, 

 sometimes in the same cavities as the levynite, sometimes in 

 separate ones. The levynite has the form of flat plates, with 

 curved irregular faces. The form is almost the same as that 

 mentioned above, as both rhombohedra and scalenohedra are 

 developed. The crystals are transparent and colourless. On 

 the north side of Gaasefjord, among many fragments of basalt 

 with chabazite, a few were found with the cavities containing 

 levynite. These crystals are quite small about 1 —2i"ni in length, 

 and of approximately the same crystal form as the preceding 

 ones. In a few cavities, a peculiar kind of crystal was found, 

 which has been observed before in West- Greenland, but which 

 I do not think has as yet been described. Both basal planes 

 are covered with a thin layer of threads of a silk-like lustre, 

 placed perpendicularly to the plane. In transverse sections of 



