Page:The New International Encyclopædia 1st ed. v. 05.djvu/452

* COPPER. 390 COPPER. follnwing table compiled for The Mint-nil In- dustry: The World's Production of Copper in 1900. COUNTI11E8 Long Tons COUNTRIES Long Tons 75 23,000 1.355 2.100 8.459 6,720 25,604 20,310 2.7,53 27,840 22.119 Newfonndland 2,883 Austria-Hungary .. "R Olivia 3,935 Russia 8,000 Peru 8.220 Cape of G. Hope.... Spain-Portugal ... 62,872 450 Turkey 2,304 United Kingdom.. United States Total 765 268.229 487,993 Copperniining has long been carried on in the United States : deposits were worked in Con- necticut, New Jersey, and Pennsylvania in the early part of the eigliteenth century, and there are "records of ore-shipments to Kngland as early as 1731. The beginning of the indu.stry in its present importance, however, may be said to date from the opening of the Lake Superior dis- trict in 1844. At this time the output of the whole country was inconsiderable, but increasing steadilv as new mines were developed; it reached 10,000 'long tons in 1807 and 27.000 tons in 1S80, Then, with thf extension of railway facilities in the West, the rich deposits of Jlontana and Arizona became accessible for exploitation and quickly assumed a prominent place in the list of producers. The Lake Superior copper-mining district on the Upper Peninsula of Jlichigan is leniarkable for its unique character as well as for its great commercial imjiortance. Tlie ore is native copper, carrying some silver, but with only small amounts of' other impurities. It occurs as a cement, binding together or replacing the pebbles of a conglomerate, as a filling in an amygdaloidal diabase, and as irregular masses in veins. The last-named deposits have yielded innnensc masses of cop])er, but, as the veins are irregular and of variable tenor, they cannot be worked at a profit when copper prices are low. The productive mines, at the present time, are located in the conglomerate or in the diabase. These deposits yield an ore averaging from six- tenths to four per cent, copper. With the lower limif. which is reached in the Atlantic mine, the operations must be conducted on a large scale and at a minimum of cost to yield a profit. The bornitc. chalcopyrite, chalcocite, and other sul- phides, carrying silver and some gold, occur as fissure veins in granite. Enormous quantities of ore averaging as high as 40 per cent, copper were discovered in some of the mines and resulted in the rapid development of the district. With depth there has been a gradual decrease in values, and the average at the present time is probably" less than 5 per cent. The Anaconda Company for several years maintained an output of over 100.000,000 pounds, and still ranks as the largest jirodueer of copper in the world. Next in impor- tance to the Lake Sujjerior and ^lontana dis- tricts are those in Arizona at Bisbee, Clifton, and Globe. The ores, here, are carbonates, oxides, and native copper. Their occurrence is limited to Carboniferous limestone and porphyry. The mining companies have the advantage of working a rich and easily smelted ore, but this is offset by the lack of water as well as of cheap fuel and transportation facilities. Besides the foregoing there are less important districts in California, Colorado, Utah, New Mexico, Tennessee, and Vermont. The following table, compiled from the sta- tistics of the United States Geological Survey, gives the copper production of the United States by decades, and shows the relative amount of the Lake Superior product: YEAH Total production Lake Percentage of Lak& in long tons Superior Superior produr-t 1845 100 12 12. 1S55 3,000 2,593 86.4 1866 .s.6no 6.410 75.4 1875 IS.ODO 16,089 89.4 1885 74,052 32,209 43,6 1896 169,917 67,737 34. 1S99 253,870 66,803 25.9 .^mong foreign countries Spain ranks first in the ]noduction of copper. Deposits near Huelva, Andalusia, have been worked since Roman times. The ore ( pyrites ) carries only 2 to 3 per cent. co])])er, but it occurs in immense deposits and is easily extracted. Chile and Mexico are im- ])ortant copper-producers and give promise of attaining greater prominence in the immediate future. The great increase in the use of copper in electrical and other industries is shown in the following table, giving, in long tons, the world's production for the decade of 1800-99: World's Production op Copper 1890-1899. .CC0RniNO TO THE t'xiTED STATES CiEOLOGICAIj Survey COrXTRY 1890 1S91 1892 1S93 1894 1895 1S96 1897 1898 1899 79,952 124,711 33,960 6.,570 11,972 9,455 80,751 138,065 29,015 6.120 18,500 10,292 84.64S li;6,'.l41 29,01.-1 0,120 19,000 8,7,85 S2.022 1.6B..553 27,320 6,090 18,000 6,168 82,474 172,994 26.810 6.,600 20.050 6,791 83,128 187,260 24,926 7.116 18.430 8,573 SS,21C 222,-624 26.340 7,460 21,000 11,272 S9,9:iS 242.679 25.300 7,440 23.000 16,583 87.960 261,626 30.065 7.110 26.175 17,043 91,105 282,636 32,7:iO 6,490 27,560 17,900 266,620 282,743 314.509 299,043 315.619 329,431 376,802 404,940 428,978 468,421 Calumet and Heda is the richest and largest of the Lake Superior mines. While this district has been an active producer for more than fifty vears, it still has a promising future, owing to the favorable conditions for deep mining. The most productive copper-mines of Montana are situated near Butte. The deposits, consisting of Copper (sj'mbol, Cu; atomic weight, 63.60) is a red-colored metal with a bright, metallic lus- tre. The specific gravity of finely divided cop- per is 8.36 ; that of hammered copper is 8.95. It is very malleable and may be hanunered or rolled into thin leaf or dra^^•n into fine wire. Its melting-point is about 1100° C, and it bums