1835.] Analysis of Nellore Copper ores. 577 



is in an almost metallic state in it. Fracture approaching to even fine 

 grained streak; of the black, brighter metallic ; powder, "greenish;" not very 

 hard, except the iron black and bluish grey part ; which is with difficulty 

 scratched by quartz ; brittle ; not particularly heavy. Specific gravity, 3.09. 

 Some pieces are found of a nut brown color, and some with conchoidal fracture. 

 The foreign admixtures are various, as white and green quartz, mica, iron ore ; 

 mountain blue and malachite are in some places found with it. In other places, 

 I suspect the admixture of silver. For the analysis, I must refer to that of Dr. 

 Thomson, in a paper laid before the Royal Society of London, which I was per- 

 mitted to publish as an appendix to my " Tracts on India." I will only men- 

 tion here, that on an average, he procured 50 per cent, of pure copper. In the dry 

 way, or by simply smelting the ore, we have received the metal in greater propor- 

 tion, which may be easily accounted for by the quantity of iron, which the ore 

 contains, that cannot be separated, as when the analysis is carried on by acids and 

 other re-agents." 



Mr. Hayne seems to have been wrong in imagining 1 , that the 

 natives had only discovered these mines 50 or 60 years before (about 

 1750). Mr. Kerr, who has since visited the whole of the mining 

 district, and examined all the formations, and the old works, with great 

 care, states, that the former excavations are of prodigious magnitude, 

 many of them occupying several hundred feet square, and having a 

 depth of 50 or 60 feet. The matrix rock and rubbish are now 

 accumulated in these immense tanks ; but on clearing them away, the 

 mouths of the galleries extending into the rocks were discovered ; 

 blocks of the ore, (perhaps some that had been gathered previous to 

 the discontinuance of working the mines from some political convul- 

 sion or oppression,) have been used to mend the village tank at 

 Guramavypenta ; and Mr. Kerr imagines, that any quantity of the 

 richest ore* may be obtained at a trifling expence, and within 100 

 feet of the surface. Extensive hills, formed of lumps of ferruginous 

 slag, now covered with vegetation, point out the situation of the 

 ancient smelting houses. A piece of this slag (which was at first 

 mistaken for a volcanic product) was analysed hy myself. It yielded 

 but faint traces of copper, shewing that the native processes of 

 extraction, however rude, were effectual in completely separating the 

 metal. But I must now proceed to observe upon the actual specimens 

 of the ore submitted to my examination, purposely avoiding all allu- 

 sion to the mercantile value of the mines, the estimates of the expence 

 of working them, and the invitations to join in an association for this 

 purpose: — objects which are highly interesting to the community, con- 

 nected with so laudable a measure for developing the natural riches of 



* The " steel-grained, crystallized silvery ore, invariably found in green-stone 

 slate, and partly imbedded in quartz, the richest ore met with," is doubtless 

 No. 3, the sulphuret. — J. P. 



