185/.] ANSTED — MINEBAL VEINS. 249 



by no means easy to determine, as they are covered by vegetable soil 

 and a growth of forest-trees. On the banks of the Ocooee towards 

 the north-west, the rocks seen consist of felspathic porphyries with 

 quartz-veins, alternating with numerous varieties of schist and blue 

 slate. Overlying these are magnesian rocks, consisting of talcose and 

 steatitic schists, which seem to abound especially in the metalliferous 

 portions of the countrv. ^licaceous schists are also common, and 

 garnet-schists are characteristic of some particular localities. Among 

 the minerals common in the veins mav be mentioned cvanite, of which 

 I saw large quantities, — epidote, not so abundant, — and common gar- 

 nets, often extremely plentiful. 



Some idea of the country will be obtained by referring to the two 

 sections, figs, h k, ^, and the accompanying map, fig. 4, p. 247, but 

 much det-^iied observation would be needed to insert accurately the 

 limits of the various metamorphic rocks, and determine the mod« in 

 which they pass from one to another variety of schist and porphyry. 



It will be seen by reference to the map that of the four gossan- 

 lodes the length varies from 600 yards to upwards of a mile. The 

 width is still more variable, ranging from 6 or 7 to 40 or 50 feet in 

 three of the number, and in the fourth averaging as much as 250 feet. 

 These dimensions have been actually proved either by the out- 

 cropping gossan or by workings on the lodes at a small depth. 

 Wherever throughout the district any portion of these gossans has 

 been sunk through to sufficient depth, they have been found to ter- 

 minate downwards in a variable thickness of black soft copper-ore, 

 which analysis shows to be derived from the decomposition of copper- 

 pyrites. The distance of this deposit from the surface varies from 

 5 or 6 up to about 90 feet, and often seems to have some imperfect 

 correspondence with the form of the ground, being usually smallest 

 in the valleys and greatest on the crests of the hills. The outcrops 

 are also narrowest in the valleys, at least in a majority of cases. 



The black ore reposes on a very irregular floor of hard dense 

 quartzose veinstone sparingly spotted with copper-ore, and largely 

 impregnated with black and yellow copper-ore. In various parts of 

 the mineral field this veinstone has been sunk through to different 

 depths, but nowhere more than 18 fathoms. No very important 

 change has been recognized thus far, but fair indications of copper- 

 lodes of the ordinary kind are not wanting, and in one place bevond 

 and to the south of the Tennessee gossan-lode there was a distinct 

 change of ground noticed, and the veinstone became calcareous at a 

 depth of about 17 fathoms from grass*. 



The thickness of the black ore between the gossan and the floor of 



* In this sinking the lode underlies from 15 to 18 inches in the fathom, its 

 width appears to be between 30 and 40 feet, and the foot-wall appears to become 

 Bofter on going down. The veinstone itself, however, remains extremely hard, 

 and the stones of copper-ore obtained were too few to be of importance, even as 

 indications. A thin seam of poor ore was found under the gossan, but where no 

 quantity of iron-oxide was seen at the surface there was nothing worth removing 

 below. In the Culchote mine the surface-indications were poor and small ; but 

 the underground appearances were more satisfactory. Ko profitable result has. 

 •however, been obtained as yet (June 1857). 



T 2 



