462 Macfarlane on the Acton Copper Mi 



me. 



The angular fragment contained no copper, but gave 



Silicious matter, 8.25 



Alumina and peroxide of iron . . . 2.75 



Carbonate of lime 73.20 



Carbonate of mas^nesia 15.50 



99.7 

 Other specimens of veinstone examined, contained as follows : — 



Silica 

 Copper 



From the various analyses made of the purple copper, it does 

 not seem to differ essentially from the variety of this mineral to 

 •which the formula Fe Cu^ S* has been given. 



I have thus described the progress of the mine, and the results 

 obtained in the various productive workings during the thirteen 

 months ending 30th September, 1862. If we take the average of 

 these results, we find that the average produce per cubic fathom has 

 been 1.6 tons of 12 per cent ore ; the average cost of mining and 

 bringing to surface, $11.28 per cubic fathom, and $7.03 per ton 

 of 12 per cent ore. These, it will be observed, are the results of 

 minino- in the produclive part of the cupriferous bed, exclusive al- 

 together of the cost of explorative work, of which latter it was 

 only in No. 2 drift that any considerable amount was done. Pro- 

 bably the cost of prospective work did not exceed $1.50 on each 

 ton of ore produced; so that we may assume that the cost of 

 searching for ore, mining and bringing it to the surface, was $8.50 

 per ton of 12 per cent. 



Before leaving this part of the subject, I may be per.nitted to 

 make some remarks as to the nature of the deposit and the source 

 of the ore. It will probably be admitted on all hands, that the 

 bed of limestone in which the ore occurs, is of sedimentary origin, 

 and originally possessed a horizontal position. Nor will it pro- 

 bably be denied, that a part at least of the copper ; viz., that part 

 which occurs in the form of copper pyrites, finely disseminated 

 through some parts of the rock, was deposited, in some state or 

 other, simultaneously with the limestone. That the limestone 

 and the rocks adjoining it have, by certain powerful agencies, 

 been raised from their horizontal position, and in this process been 



