Silver

a lustrous white metal ten and one-half times as heavy as water. It is not acted on by air, oxygen, or water. The tarnish of silver spoons used with eggs, fruit, or acquired in a coal-heated house, is derived from a trace of sulphur, for which silver has a strong affinity. As a consequence, silver ores are usually a compound of silver and sulphur with a third metal, as lead, zinc, copper, or arsenic. In fact a percentage of silver is often relied upon for the sole profit in working many lead and copper mines. Sometimes silver occurs free from other metals. It then takes the form usually of cubes or else eight-sided masses, or again the silver may occur in a fibrous mass. One piece of silver in the Copenhagen Museum weighs 500 pounds.

The greatest single silver vein ever known is the famous Comstock lode of Nevada. Since its discovery in 1858, it has yielded over $335,000,000 worth of silver and gold. Virginia City and practically the state of Nevada were built up on the wealth of the Comstock. The vein consists of a belt of quartz several hundred feet wide and about 10,000 feet long descending to unknown depths. Unaccountable heat, bad air, and water render it difficult to work the Comstock lode at the depths to which the miners are now required to go, and production has fallen off from $36,000,000 in 1877 to possibly a present thirtieth of that sum. Colorado now leads the Union in production of silver, notably from lead ores in the Leadville district. The Coeur d'Alene mine of Idaho yields a large amount of silver from lead ores. Montana copper ores, largely at Butte, yield silver. Other silver-producing states are named in the following table of production for 1908:

The reputation of the New World for silver, though ably sustained by the United States, was made really by Mexico and the countries of the Andean region. The almost fabulous mines of Potosi, in Brazil, discovered in 1545 and worked more or less continuously until 1850, have yielded over $3,000,000,000 worth of silver. The chief silver-producing countries are shown in the following table of the world's production of silver for 1907: North America- United States . . . . . $38,445,236

Prior to 1873 silver was readily exchangeable for coin at a fixed price, but about that date the leading countries decided upon gold as a single standard, and silver has since sold like lead and iron at whatever price it could command in the market. The average commercial value of silver for 1908 was fifty-three cents per ounce.

The chief consumers of silver are the manufacturers of jewelry and silverware. Silver is a beautiful but expensive metal for outdoor trimmings. It is exceedingly desirable for that purpose except in districts where various industries, involving the consumption of coal, liberate sulphur-laden gases, which, as stated, tarnish silver.

Silver is not only an ornamental but a useful metal. It is still used as an alloy in gold coinage, and large quantities of silver coins are issued by the various governments. At the present time four ounces of silver are sufficient to make nearly five silver dollars, or, to be exact, 10,000 ounces of silver make 12,929 silver dollars. Coinage silver is alloyed with copper to make it wear better.

See Gold; Peru; Mexico; Aztecs