 The losses of copper in the above-described roasting have been very generally ignored in judging of its expense. At least, proper emphasis has never been laid on them. Owing to an unexplained difference of several hundred thousand pounds between the fine...  Modern American Methods of Copper Smelting - Pagina 107door Edward Dyer Peters - 1891 - 398 pagina’sVolledige weergave - Over dit boek
 | 1886 - 530 pagina’s
...ton of ore was as follows : ^5 cord wood, (n, $3.00, . $0.15 Labor, 1st fire, .......... .10 " 2d " 14 Materials, ........... .03 Total per ton, $0.42...at by deducting one and one-quarter unit from the assay-value of the ores produced, the writer's attention was forcibly called to this subject. A careful... | |
 | 1886 - 436 pagina’s
...vroocl, @ Sj-oo, ......... §0.15 Labor, 1st 6re, 10 " 2d " 14 Materials, 03 Total per ton, ...... §0.42 The losses of copper in the above-described roasting...at by deducting one and one-quarter unit from the assay-value of the ores produced, the writer's attention was forcibly called to this subject. A careful... | |
 | Edward Dyer Peters - 1903 - 714 pagina’s
...A cord of wood at $3 $0.15 Labor, 1st fire 10 Labor, 2d fire 14 Materials 03 Total, per ton. |0.42 "The losses of copper in the above-described roasting have been very generally ignored in jndging of its expense. At least, proper emphasis has never been laid on them. "Owing to an unexplained... | |
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