| Coke | $1.47 |
| Fluxes | 0.04 |
| Labor | 0.65 |
| Coal for power | 0.10 |
| General expenses | 0.17 |
| Total | $2.43 |
This $2.43 per ton includes all expenses of whatever kind. The iron carbonate flux contained lead and silver, which was not paid for. The fluxes are credited for the actual value of this lead and silver. Without making this discount, the cost of flux would amount to 26c. per ton, making the entire smelting cost come to $2.65. As an explanation of the low cost of labor, it may be noted that the wages were, for the furnace-man, 2.25 pesetas, or 32c. a day; for the helpers, 1.75 pesetas, or 25c. a day.
The basis for purchasing the galena ore may here be given, reduced to American money; lead and silver are paid for according to the latest quotations for refined metals given by the Revista Minera, published at Cartagena. (The quotations are the actual value in Cartagena of the London quotations.)
The following discounts are made: 5 per cent. for both silver and lead; $6.40 per ton on ore containing 7 per cent. Pb and below; this rises gradually to a discount of $7.75 per ton of ore containing 30 per cent. Pb and above.
The transportation is paid by the purchaser and amounts to about $1.20 per ton of ore.
The dry silver ores were cheaper than this and the lead carbonates much more expensive.
LEAD SMELTING AT MONTEPONI, SARDINIA[59]
By Erminio Ferraris
(October 28, 1905)