122 Macfarlane on the Primitive Formations 



important. It has a thickness of from four to thirty inches ; the 

 vein-stone is quartz, and is well filled with copper pyrites, generally 

 massive, seldom finely disseminated. In the deeper workings, the 

 lode almost contains as much purple copper as copper pyrites, with 

 no admixture of iron pyrites, or other mineral, except a little feld 

 spar. The ore, on being excavated, was crushed by flat-faced 

 hand hammers, brought up, by jigging, to 30 per cent., and 

 then smelted or sold. Nsesmark mine is like HofTnung, situated 

 in the immediate neighborhood of the work, on a granite vein, 

 two fathoms thick, which intersects primitive slates. In this vein, 

 (from which also side veins shoot out into the adjoining slates,) 

 there occur, running in a direction at right angles with its line 

 of strike, numerous lodes of from two to six inches thick, filled 

 with quartz and copper glance; the latter containing six oz. of sil- 

 ver per cwt. The granite in the neighborhood of these quartz 

 veins is also impregnated with copper glance , to such an extent, 

 as to make it amply worth stamping and washing. This mine is 

 a most promising one ; is altogether new, and the granitic vein has 

 been discovered at a distance of three miles from it, at Bergland 

 mine ; where it bears copper glance in exactly the same manner 

 as at Nsesmark. The ore from the quartz lodes of this mine was 

 brought up by hand-jigging to 70 per cent., and then either 

 smelted or sold. The finely divided ore was worked by stamping 

 and washing. Mosnap mine is about 10 miles distant from the 

 work, and probably lies 2000 feet above the sea. The rocks in 

 the neighborhood are the gneiss, mica schist, and hornblende 

 schist, peculiar to the quartzose group. The mine itself is situ- 

 ated on a granitic vein,which contains irregular quartz layers. Cop- 

 per pyrites, purple copper, and molybdenite are disseminated 

 through it, bat are more especially associated with the quartz. 

 The vein itself has a thickness of several feet, and were it more 

 conveniently situated, would doubtless be considered a very valu- 

 able deposit. It is only very lately that the ores from these mines 

 began to be treated by crushing and jigging, and then sent to 

 market. They were previously stamped and washed, at least the 

 poorer sorts, and the products were smelted at the works, 

 along with the richer ores. The smelting, however, even after 

 the discovery of a vein of fluor spar, which was used as flux, was 

 carried on but with indiff'erent success, on account of the highly 

 quartzose natures of the ores. After the introduction of jigging, 

 the ores were treated as follows, at the smelting works : — The 

 copper glance from Najsmark was calcined in a reverberatory 



