APP. N** VI.] MINERALS OF SriTZBKIlCEX, (77) 



Mica-slate. » 



Mica-slate passing into clay-slate. 



Quartz-rock. 



Rhomboidal calcareous-spar. 



The gneiss was of a grey colour, the felspar and quartz 

 being both grey, and the mica dark blackish-brown. Some 

 varieties were very coarse granular and inclining to granite ; 

 but no true granite was met with. The mica-slate had the 

 usual characters of that rock. The quartz-rock was grey, 

 small granular, and in some specimens splintery. Some 

 masses contained disseminated scales of mica, but no felspar. 

 In both varieties of quartz-rock observed, were minutely dis- 

 seminated iron-pyrites, which decaying of a yellowish-brown, 

 tinged the rock of that colour. The calcareous-spar occurred 

 in veins in the limestone. It was found only in the roof of a 

 deep cavern. 



From these specimens, which were all the varieties met 

 with in two or three excursions to the shore, it appeared to 

 Professor Jameson that the mountains and shores of Spitz- 

 bergen visited by me, are formed of gneiss, mica-slate, and 

 quartz-rock, which contain great and frequent beds of bluish- 

 coloured limestone. No secondary rocks, such as sandstone, 

 basalt, clinkstone, or others of a similar description, nor any 

 rock of volcanic formation, were met with. In this respect 

 Spitzbergeii is remarkably distinguished from Jan Mayen*, 

 where all the rocks are secondary trap or volcanic. 



Nova Zembla is said to have the same geognostical features 

 as Spitzbergen ; and West Greenland abounds in primitive 

 rocks, but contains few species of the secondary class. Pro- 

 bably Spitzbergen and Nova Zembla, were formerly more 

 intimately connected than they are at present. 



* Cherie Island appears to be composed of the same rocks as Jan Mayen. 



