GIESECKK ON THE GEOLOGY OF GREENLAND. 331 



which occur in this rock on the mountain Kingiktorsoak have 

 been ah-eady mentioned. Hornblende-slate, forming beds in mica- 

 slate, is found in many places. 



In the 64th degree of latitude, in a firth called Ameraglik, in 

 the south of the Dfinish colony Godthaab (Goodhope), a variety 

 of mica-slate is found, which passes into talc-slate, forming a very 

 small layer in coarse-granular granite. It is very remarkable, on 

 account of the large groups of tourmaline which occur, imbedded 

 or rather involved in talcose mica, and which are the largest crystals 

 of this fine mineral that have been met with. At the end of the 

 same firth, at Auaitsirksarbick, in the neighbourhood of the great 

 continental glacier, the finest garnets are found. They are of a 

 lamellar texture, and surpass the oriental specimens in colour, 

 lustre, and hardness. At the same place, dichroite and hyperstene 

 of a beautiful blue colour occur, along with precious garnet, in 

 decomposed mica-slate. All the lower mountains from the 66th 

 to the 71st degree of north latitude, and particularly all the 

 mountains of the continent forming Disko Bay, with the greatest 

 part of the adjacent islands, are composed of mica-slate. There 

 is scarcely a square mile where the rock is entirely free from 

 garnets. A large mountain in Omenaks Firth, called Sedliarusaet 

 presents on its surface only the powder of mica-slate, and frag- 

 ments of precious garnet. From the appearance of this powder, 

 it is probable that the rock formerly contained great masses of 

 imbedded iron-pyrites. No snow rests on the surface of this 

 mountain in the coldest winter. The fragments of precious 

 garnet which are found here, when clear, are the most highly 

 prized of any on the coast. Other minerals which are found in 

 mica-slate in Greenland are emery, on the island Kikertarsoeit- 

 siak in South Greenland ; granatite, on the island Manetsok ; 

 moroxite, in very large six-sided prisms, at Sungangarsok, in 

 North Greenland ; and dichroite in six-sided prisms on the island 

 Ujordlersoak, in the 76th degree N. lat. Except iron-pyrites, 

 copper-pyrites, and galena, no metal occurs in this rock. 



White Stone (Weiss-stein), which has lately been determined 

 by Werner, appears to belong to this rock. It presents a white 

 and greyish-white granular appearance, which was formerly 

 supposed to be compact or granular felspar. It is in this country 

 characterised by very small and minute crystals of garnet dis- 

 seminated through the whole mass. Here it is found in layers of 

 inconsiderable extent, resting on mica-slate, very seldom on gneiss. 

 It is also found in detached pieces. 



4. Clay-slate is very seldom met with on this coast, and 

 consequently the different beds which are characteristic of this 

 rock, viz., flint-slate, lydian-stone, alum-slate, but rarely occur. 

 Nevertheless, at the mouth of the Firth Arksut it forms two islands 

 of some importance, called Arksut and Ujorbik. The colour of 

 the slate is ash-grey and bluish-grey ; its fragments present a 

 double cleavage ; and it is traversed in all directions by numerous 

 veins of massive and crystallised quartz, massive hornstone, and 

 sparry-iron-ore of an isabella-yellow colour. An extensive bed 

 of flinty slate and lydian-stone rests upon it on the east side of 



