PRECIOUS METAL INDUSTRY IN THE UNITED STATES. 59
continental railway lines cross the Territory from east to west, but have few branches, the greater part of the region not being able to support anything more than the sparsest population.
Detrital material is accumulated in very considerable quantities in some of the valleys, especially in the central part of the Territory. Many of tliem contain considerable amounts of free gold, but the scarcity of water in most cases forms an insurmountable obstacle to their development. Some attempts are said to have been made to utilize the water of the Colorado river in working neighboring placer gravels, but with what success is not reported.
The product of the Territory may be, therefore, assumed to come almost exclusively from deep mines. The statistics of production show a fairly steady annual output of gold amounting to about a million of dollars in value, while the product of silver has decreased with remarkable regularity from over seven millions at the beginning of the decade to about a million and a quarter at its close. The most important silver-producing region has been the Tombstone district, in the southeastern part of the Territory, where silver-lead deposits in limestone, associated with eruptive rocks, commenced producing early in the decade. The product of the county (Cochise) in which these mines occur is said in 1S82 to have been as much as $000,000 in gold and over $5,000,000 in silver, and in 18913 to have fallen off to about a tenth of these amounts, respectively.
Silver-lead deposits have been developed in other parts of the Territory to a ceitain extent, and do not appear to have been entirely confined to limestones, which may account for their relatively small and uncertain production, for it is in these rocks that the immense bodies of lead and silver ores yielding annual products of several millions in value are usually found.
Arizona undoubtedly possesses great mineral wealth and abundant stores of precious-metal ores, but in the absence of any definite geolog ical knowledge with regard to them it is impossible to intelligently account for the decrease in the product. Probably the want of such knowledge has been a factor in this decrease, since capital is with difficulty induced to invest in the unknown. Other probable causes are to be found in the physical character of the region, a want of abundant and cheap transportation facilities, and the absence of local supplies of coal, all of which render the cost of mining and of reduction of the ores relatively high, so that only exceptionally rich ores yield a profit to the miner, and such ores are generally in small amount and rapidly exhausted. An abundant supply of low-grade ores is the surest basis on which a permanent mining industry can be found. With a falling price of silver the outlook for precious-metal production in the Territory must therefore be considered most unpromising, for successful gold mining is, as a rule, even more dependent on low costs than silver mining.