348 TAYLER ON THE TIN-ORE AT EVIGTOK. 



XL VI. — On the Veins of Tin-ore at Evigtok, near Arksut, 

 Greenland. By J. W. Tayler, Esq., F.G.S., Mining 

 Engineer to the Greenland Mining Association.^ (Re- 

 printed, by Permission, from the Quarterly Journal of 

 the Geological Society of London, vol. xv., 1859, 

 pp. 606-7.) 



The area over which the veins of tin extend is about 1,500 feet 

 in length by 80 in breadth; their number is 18 or 20; and 

 they run in various directions, some E. and W., others N.E. 

 and S.W., or N. and S. The tin occurs also disseminated in 

 crystals through the rocks, and accompanying the finer-grained 

 galena and tantalite. The appearance of the veins at the surface 

 is not very promising, the tin being in small detached crystals, 

 scattered through the gangue (which is mostly quartz). The 

 widest of those veins is 10 inches, the tin being 1 or 1^ inch, occu- 

 pying one side of the vein. The gangue here is felspar, quartz, 

 sparry-iron (carbonate of iron), and fluor-spar. This vein runs 

 E. and W. into the white cryolite. Another vein, about 200 feet 

 west from the cryolite, is visible for about 30 paces ; at the 

 surface it is not more than ^ of an inch thick, but at a depth of 

 6 feet it is 3 inches thick. Other veins are at the surface mere 

 strings, varying from J to :J of an inch thick. Nearly all these 

 veins occur in a large vein or bed of felspar and quartz, some of 

 the crystals of the latter having a diameter of 18 inches. This 

 mass contains, in a limited space, various other minerals, such as 

 galena, blende, copper-, iron-, and arsenical pyrites, fluor-spar, 

 black cryolite, tantalite, molybdena, sparry-iron, zircon, &c. 



There are some peculiarities connected with these tin-veins 

 which deserve consideration, and would lead one to expect that at 

 a greater depth they might aff'ord a large produce. The only 

 surface vein which can be seen sectionally (no sinkings having 

 yet been made) widens rapidly as it descends ; and in other spots 

 sectional views of two small veins are to be seen which do not 

 reach the surface. The most remarkable of these is a vein which 

 I found in the floor of a small cavern. It consisted at first of 

 sparry-iron, arsenical pyrites, fluor, &c. ; a few feet deeper it 

 changed its character, and contained good traces of copper ; but 

 water prevented us following it deeper : it is here about 15 inches 

 wide. The minerals accompanying the copper are those usually 

 met with in good and productive veins, besides the black cryolite, 

 which is here peculiar to it. 



These veins, in my opinion, evidently belong to the under- 

 lying granite, which appears at the surface in veins, and which is 

 probably at no great depth below, since the tin-veins penetrate 

 into the overlying gneiss, which dips to the south, and under the 



* For Mr. Tayler's remarks on the cryolite of Evigtok, see Quart. Journ. 

 Geol. Soc, vol. xii., p. 140 ; and above, p. 344. 



