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History.---Lead mining in the United States goes back to 1621 , when lead ore was mined and smelted near Falling Creek, Va. Lead production in this country for the next 200 years, while fairly steady, was comparatively small; the entire output for the second 100 years (1721 to 1820) was only about one-seventh the output of a single year at the beginning of the twentieth century.8
The lead mines of Wisconsin were discovered about 1820, and for 50 years were the dominant factor in the rapidly increasing American production. While the Missouri mines furnished a good deal of lead through this period, they were much less important than the Wisconsin operations.
The domestic production of lead in 1870 was 17,830 short tons, consisting wholly of soft lead produced from nonargentiferous ores. The first discovery of argentiferous lead was made in 1863 in Utah. Development of other silver-lead mines in Utah, Colorado, Idaho, and other Western States followed rapidly as soon as transcontinental railroad communication was effected.
Since 1870 the domestic production of lead has increased steadily, with almost no setbacks. In 1880 the output was 97,825 tons, more than five times as much as in 1870. The increase was due almost entirely to the great output from silver-lead ore. In 1890 the total production was 143,630 short tons and in 1900 it was 270,824 short tons. This steady growth, amounting to nearly 90 per cent every decade, is attributable almost wholly to the increase in the production of desilverized lead. The increase in the production of soft lead was only 48,021, or about 170 per cent, in the 30 years.
The development of the Rocky Mountain lead districts reached its zenith in 1906 and the production has not much more than held its own since. On the contrary the growth of the soft-lead districts of
. the Mississippi Valley has been steady and sure and is again becoming the dominant factor. Since 1900 the production of soft lead has increased much faster than that of desilverized lead. In 1910 it was nearly three times as great as it was in 1900, whereas the total output for the latter year, amounting to 375,402 tons (from domestic ore), was only 40 per cent greater than that in 1900.
Domestic production and consumption.-Since the capacity of furnaces for smelting lead ore is based on the number of tons of charge, the total capacity of the American lead furnaces (5,521,000 tons in 1918) bears no relation to the lead contents, nor even to the number of tons of lead ore that can be treated annually in this country. Under the conditions existing in 1908 to 1911, prior to the outbreak of political troubles in Mexico, the amount of lead produced from foreign ores in American works was about 25 per cent of that produced from domestic ores. On account of the high tariff protection, very little of this material was consumed in this country, bat was exported under the bonded smelting provision with benefit of drawback. Of this total crude material the proportion of ore was gradually decreasing as compared with the amount of bullion. Separate statistics of imports are not available prior to 1906, but in 1908 the amount of base bullion imported increased 100 per cent,
€ A detailed chronology of lead mining in the United States from 1621 to 1906 wi'l be found in Ingalls' Lead and Zinc in the United States. McGraw-Hill, 1908, PD. 28–36. This chronology may be brought up to date from the general chronology of minin; published periodically by the Engineering and Mining Jour.
7 Hofman, H. 0.: Metallurgy of lead. McGraw-Hill, 1918, p. 2. 8 Ingalls, W. R.: Loc. cit., p. viii.
whereas the importation of lead ore was little affected. The average lead content of ore imported annually from 1907 to 1910, inclusive, was about 37,000 tons, or less than 10 per cent of the average domestic mine output during that period.
It was not until 1916 that any considerable foreign ore was again treated in American works, but even in 1918 the lead content of imported ore was only 3.3 per cent of that in the domestic mine production. The imports of base bullion in the latter year, however, were up to the prewar level. In 1920, the imports of lead in ore were only 15,000 tons and in bullion about 49,000 tons, a total of 64,000 tons as compared with 65,799 tons in 1919 (fiscal years).
Net consumption of foreign lead ore showing general imports for comparison), imports for consumption (except those admitted free of duty for smelting in bonded works), duties collected, and ecports with benefit of drawback (uith the amount of drawback paid), net consumption and net revenue.
1, 151, 503 17, 115.47 833, 715
4,618, 255 12, 505.73
69, 995.91 280, 661 4,832.58 553, 054 885, 714 13, 283.73
7,673.15 83, 397 1,238.39 4,311, 827
802, 317 12, 017.34 32,985.69 331, 877 2, 900.6+ 3,993, 167
3,976, 950 30,085.05 29, 918.75 6, 711, 757 50, 515.70 (2,748, 590) [20, 366.95] 6, 500, 793 51, 005.99 2,071, 248 15, 43.99 8,433, 649
4,729, 515 63,252.39
35, 562.10 921, 197 6,839.99 5, 242, 450
7,312, 152 56, 412.50 39,318.12 3, 507, 735 26, 014.86 1,734, 715 13, 273.36 12, 423, 272 421, 132.15 22, 39.5, 357 233, 365.86 20, 027, 915 187, 766.29 4,713, 697 46, 792.16 2, 188, 373 25, 929.54 2, 225, 324 20, $62.92
* Data from Commerce and Navigation, Department of Commerce.
* Obtained by subtracting “Exports with benefit of drawback” from "Imports for consumption (dutiable).” Figures for 1910 and 1915 (bracketed) are negative, due to overlap from previous years.
NOTE.-On account of the bonded smelting proviso and since there are no exports of foreign lead in the form of ora, the net consumption of foreign ore in smelting works equals the general imports. The net consumption as shown in this table represents, therefore, only the lead ore that is smelted in this country for domestic consumption of the metal produced. Formerly the records of the Department of Commerce showed ' Foreign exports" of lead ore, but these exports actually consisted of lead metal produced from imported ore and carried on the records in the form in which it was imported. Since July 1, 1915, however, the e exports have been recorded under “Domestic exports" and described as “lead produced from foreigni ore."
Domestic exports. In the early history of lead mining in the United States, some high-grade ore was shipped to Europe for smelting; but after the smelting facilities of this country became adequate there was no reason for exporting crude ore. Except for a small amount that occasionally crosses the border consigned from Washington mines to the near-by smeltery at Trail, B. C., no ore is known to have been exported for fully 30 years.
Lead is mined in nearly all the countries of the world, but fully 80 per cent of the entire output comes from five countries. In order of output in 1913 these countries were: United States, Australia, Spain, Germany, and Mexico. Under the stress of war conditions this order undoubtedly changed. The probable great increase in
German output and a curtailment in Spain resulted in reversing the slight differential previously existing while in 1913 the Mexican output was considerably below normal. It may be expected to soon regain its customary position as fourth largest producer, if it has not already done so.
The resources and mining in the various countries are briefly discussed in the auxiliary file. Broadly speaking, the only countries that compete with the United States output in the domestic ore market are Mexico, Canada, and Chile. Except locally, serious competition comes only from Mexico, and this is now becoming less a factor with the development of smelteries in Mexico nearer to the sources of supply, Mexican lead ore, however, is a powerful potential factor. It is high grade, generally rich in silver, and (in spite of its frequently high zinc content) is at leust as desirable as the domestic ore from the standpoint of the smelter. Except for the duty, it can be obtained cheaper than domestic ore. Mexican lead deposits are controlled almost entirely by American companies, chief among which are the American Smelting & Refining Co and the American Metal Co.
Countries of origin.-Mexico is the largest contributor of lead ore as it is of lead bullion. A large part of it comes from northern Sonora and Chihuahua, sections that are geographically tributary to the El Paso smeltery. Sporadic shipments come from Canada from the Provinces of Quebec and British Columbia. In general, they represent overflow production beyond the capacity of the local works. Comparatively large imports have been received from German Africa in late years. Chile is the only other contributing country of any importance.
Quantity.-The imports of lead ore have fluctuated to a marked degree. The maximum importation for any fiscal year was in 1906, when 70,702,321 pounds of lead were imported for consumption in the form of ore.
Under the then-existing tariff of 1} cents per pound the duties collected on this importation amounted to $1,060,534. After deducting drawbacks paid the net revenue amounted to slightly less than $1,000,000.9
Since 1906 imports have greatly decreased. The following year the imports for consumption fell to less than 30,000,000 pounds, and in 1908 the imports for consumption amounted to less than 4,000,000. The statistics for general imports of lead ore prior to 1910 also include the imports of base bullion. The totals fell from some 207,000,000 pounds in 1905 to about 128,000,000 in 1907 and then increased again to 226,000,000 in 1909. Due to the growing importance of base bullion due to the opening of smelteries in Mexico, which in 19061900 was rapidly diverting the Mexican lead from American smelteries, the general imports of this material were increasing in proportion as those of ore were reduced. Base bullion has been recorded separately in the general imports statistics since 1910.
As the Mexican smelteries increased their output, more and more of the Mexican lead came to the United States in the form of base bullion (to be refined) instead of in the form of ore.
9 For several years preceding and after 1906 the exports with benefit of draw back were practically the same as in 1906, indicating that this record amount was actually consumed in this country.
Character. The import figures since 1911 showing both the gross weight and the lead contents of imported ore indicate a wide variation in the tenor of the lead ore imported. In recent years the imported ore has not been rich in lead. This has been especially true of Mexico, where, because of the disturbed political conditions, the precious-metal ores containing smaller amounts of lead now constitute the chief output. In 1911, the last year in which Mexican mining was on a normal basis, the ore from that country averaged nearly 40 per cent lead. The general average of all imported ore in that year was nearly 28 per cent. The marked decrease in both quantity and lead tenor of Mexican ore resulted in a lowering of the general average lead content of ore imported in the next few years to less than 18 per cent.
In 1918-19 the general average was increased to about 21 per cent by large receipts of Canadian concentrates containing 65 per cent lead.
Domestic consumption of foreign ore-Revenue.10—Since practically no lead ore of either domestic or foreign origin is exported from the l'nited States, the actual consumption of foreign ore by American smelting works is represented by the statistics of general imports. On account of the privileges of bonded smelting and of export of more or less finished products with benefit of drawback on the raw materials that enter therein, certain complications arise in regard to the revenue collected on imported lead ore and the determination of the amount of lead produced from this ore that is ultimately consumed in the United States.
The lead contents of ore imported in the years 1910-1918, inclusire, averaged over 38,000,000 pounds annually. Less than 12.5 per cent of this amount was imported for consumption by payment of duty, and more than one-half of that was exported with benefit of drawback. The average net consumption, therefore, amounted to only slightly more than 2,225,000 pounds of lead (without correction for smelting losses) annually. Thus we find that in this 9-year period less than 6 per cent of the total lead contents of imported ore was actually used in the United States.
This small percentage, however, is all that yielded any revenue to the Government (neglecting the 1 per cent withheld on drawbacks). The total net revenue in the 9-year period was only $187,766.29, and under the reduced duty of the act of 1913 the average revenue (19151918, inclusive) was less than $21,000.
Except in the Mississippi Valley, lead ores are not quoted on a base price per ton, but are settled for under contract, the price varying with the assay value of the ore and the market price of the lead (and other contained metals), with certain deductions for harmful impurities, etc. The problem of ore buying is discussed at some length in the auxiliary file. On the basis of a New York price of 5 cents per pound for lead, the value to the miner of 1 pound of lead contained in ore varies from less than 2 cents for low-grade ores to about 3 cents for high-grade ore. Since the price paid for ore of a given com
. position is purely a function of the market price of the metal, and, except in the Valley States, there are no fixed standards as to tenor of ore (except that richer ores are worth more per unit of lead content), lists of prices would be valueless.
1. The preceding table should be referred to in connection with these remarks.
The phrasing of the tariff relating to lead was clarified in the McKinley Act of 1890 to the extent that silver ore containing lead definitely came within the meaning of the act, and the duty was levied specifically on the lead contents rather than upon the total weight of the ore, as might be construed from the careless wording of the previous acts. The act of 1890 was the first American tariff law in which was introduced the privilege of bonded smelting. This was a concession to the general sentiment that American smelters required more lead ore than could be got from domestic mines in order to cope with the steadily growing tonnage of dry and siliceous ores. This privilege enabled the smelters to get their muchneeded fluxing ore, but greatly reduced their margin on it, because they could no longer sell the metal at the American price without payment of duty. (The Europen price of lead was then much lower than the price on the domestic market.)
The act of 1894 cut the duty on lead ore (and dross which was classed with ore in this and several other acts prior to that of 1897) in half. The imports increased noticeably. This increase was not checked by the return in the act of 1897 to the old rate of 1} cents per pound of lead content (as compared with three-fourths cent in 1894) and, therefore, can not be attributed to the tariff changes.
In addition to increasing the duties on lead in ore and other forms the act of 1897 made a great change in the phraseology of the section relating to lead ore, by imposing duty on lead content and by providing in detail for the determination of the assay value without extra inconvenience to the consignee, allowing the sampling to be done at the latter's works under the supervision of Government officers.
In this same act an allowance was made in the paragraph dealing with bonded works, for the losses incurred in treatment. Hitherto no allowance had been made for these inevitable losses and an amount of lead equal to the total lead contents of the ore imported had to be set aside each day for cancellation of the bond. But under the act of 1897, only 90 per cent of the imported metal lad to be thus reserved.
in the act of 1909 no change was made in the tariff relating to lead ore except as regards the allowance made for smelting losses. Claims had been made that the 10 per cent loss allowance was excessive and that it allowed the free importation of lead which, although presumably lost in the slag, actually was recovered in many works. With a view to prevent such free importation the 1909 act provided that the bond was to be cancelled only upon the exportation (or withdrawal for consumption with payment of duties) of the actual quantity of lead produced from the ore (this provision also applied to base bullion).
This change made it compulsory for the Treasury Department to ascertain the exact recovery of lead. The result of these investiga
11 Gold and silver ores that contain neither lead nor copper.