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Popular Science Monthly/Volume 73/September 1908/Silver



PREVIOUS to 1870 silver was reckoned as one of the precious metals, and possessed, by virtue of an unwritten agreement between the principal nations of the world, a definite value in terms of gold, viz., $1.29 per fine ounce. The metal was never purchasable at less than this figure, and usually commanded a premium, which, during the last century, ranged from nothing up to as high as ten per cent. It is now purely a commodity, like all the other metals except gold, and while the demand has greatly increased since the date just mentioned, the production has nearly quadrupled, and the price has fallen steadily until during last year it averaged 65 cents.

Curiously enough, since this great change silver has become one of the three metals (nickel and copper being the other two) that circulate as coins at a valuation far above their commodity price. This of course is due to the fact that they are by law legal tenders up to certain amounts, but the circumstance illustrates quite well the vagaries of human law when it comes into conflict with those of nature. The American quarter, the English shilling, the Latin Union franc, the German Mark, the Austrian Kroner, the Russian Rouble, all being coins that circulate freely at valuations ranging from twenty to twenty-five cents of our money, would bring, if melted and sold as bullion, little more than half those figures. On the other hand, the Indian rupee, of approximately the same weight and fineness, not being backed by any such law, circulates at its commodity value only, and its purchasing power in the markets of the world fluctuates with the price of the metal.

Silver sometimes occurs in nature in the metallic condition, and it is due to this fact that it has been known from very ancient times. But it is not found like gold, in grains or nuggets in the gravel of stream beds. Its principal habitat is the vein in rock, and hence it may be inferred that in antiquity the quantity possessed by man was much less than that of gold. To primitive man the latter metal was regarded, in a way, as a fragment, or at least a representative of the sun, while silver bore the same relation to the moon in his mind.

When the interior of China becomes well known, it is likely that the remains of very ancient silver mines will be found there, for the metal has been produced in that nation, in small quantities, from remote antiquity. There are no evidences that India ever possessed any silver mines of note, but in Burmah there have been found extensive slag dumps rich in lead and zinc, and carrying a notable per cent, of the white metal, whence it may be inferred that it was produced there in some quantity at some time in the past. In the little known and very rugged region between Hindustan, the Persian Gulf and the Caspian Sea, embracing the crude nationalities known as Persia, Armenia, Afghanistan and Baluchistan, there has been a small production ever since early historic times, and the same may be said of Asia Minor. The Grecian peninsula, however, possessed a silver-producing region of great importance and high antiquity, from which, as early as 1000 b.c., the metal came in notable quantity. There are no known ancient silver-producing districts of any note in Africa, but the Italian peninsula and Spain yielded the metal in early historic times, the former moderately and the latter very abundantly. In fact, Spain was really the first great silver-mining country of the world.

More than any other metal silver has been intimately associated with the advance of civilization, or rather of that very important department of human activity that is called commerce, meaning thereby international trade. Authentic history seems to begin with the fact of two comparatively peaceful, industrious and frugal races, occupying the rich valleys of the regions now called India and China; and a lot of turbulent, migratory people in western Asia, eastern Europe and northern Africa, who devoted much of their time and energy to fighting and destroying each others' homes. Between the two was the highest and most difficultly passable mountain chain in the world, known now as the Hindoo Koosh and Himalaya Range, which for centuries, and perhaps millenniums kept them apart effectively enough to allow each to develop its own peculiarities. The first, which we distinguish as the Orientals, appear to have settled down at a very early period to agricultural pursuits, and to such peaceful arts and occupations as were naturally the outgrowth of ruralism. Population grew fast, a crude and quiet, yet strong trading capacity developed, religious advance was marked, but was not of the proselyting kind, was more contemplative and introspective. The arts progressed only to a certain point, and then became stationary. Wealth was attained by industry and accumulation mainly, and did not often arise from exploration or conquest. Such luxury and ease as resulted never passed much beyond the barbaric stage. The sciences did not become exact or even organized, and have retained, up to the present day, an air of mysticism. Literature was of the contemplative kind, and produced only a most cumbersome methods of recording itself.

The second, which we may call the Occidentals, advanced along wholly different lines. Every department of life was more strenuous, and the results, naturally, were more notable. The increase of population was perhaps as great, but the destruction of life by wars and slavery was enormous. The arts flourished, especially architecture, but their product in the shape of buildings, highways, canals, libraries and museums was continually being looted by conquerors, yet this very ruthless destruction seems to have incited rather than discouraged advance and improvements. The sciences were developed up to the point where discovery began, literature to the stage, where it became imperishable because of the invention of comparatively simple methods of writing, society to a state where education was highly prized, religion to the conception of monotheism.

Between these two diverse and different kinds of humanity a trade slowly sprang into existence. It was first, doubtless, by way of the Arabian Sea, which at some time in the distant past was a "mare clausum," a Mediterranean, as the result of a land connection between east Africa and India, by way of Madagascar, the Seychelles and Andaman Islands; and later by caravan routes through the passes of the mountains. The western nations sought the luxurious and decorative products of the eastern, their fabrics of silk and wool, their manufactures of bronze, their gems and jewelry of ivory and jade. What could be given in exchange? It was early discovered that the money of the east was silver, that it was scarce there and its purchasing power great. Consequently when the strenuous west began to produce the metal in quantity, first from the mountains of Persia and Asia Minor, and later in Greece, Italy and Spain, it became possessed of an article with which the products of the east could be obtained. But the west loved war above all things, and had the warrior's immemorial contempt for trade, and so there gradually grew into existence, at the extreme eastern end of the Mediterranean, a nation of traders, the Phœnicians, who took charge of the commerce between the Occident and the orient, who never gained any celebrity except along commercial lines, and who for centuries were actually protected in turn by all the great powers of antiquity because of their trading ability, and their knowledge of where and how to get those products of Asia that Europe wanted. We know that the ships of Tyre and Sidon ransacked the shores of the Mediterranean for silver, and were the owners and operators of mines of that metal in Greece, Italy and Spain. Their product was sent overland by caravan, or over sea by ships sailing from ports first on the Persian Gulf, and later on the Red Sea, to India, and exchanged for the manufactures of the east. One of the most valued of these was tin. Malaysia has been from the most remote antiquity, and is to-day, a prolific producer of this metal, and very early in the history of the human race the extremely desirable qualities of the alloy it made with copper (bronze) became known. For many centuries primitive Europe poured its silver into Asia and sold it for tin. In due time the demand became greater than the supply, and at the same time the product of the European silver mines began to fall off. The price of tin in terms of silver increased greatly. So also did the value of silver. In this crisis, which threatened the very existence of the trade between the east and the west, two remedies were tried. The Greeks, the dominant nation of the time, under Alexander the Great, started out to conquer India, and to find and capture the Asian tin mines, but, as we know, he never got any farther on the way than the valley of the Indus in eastern Hindustan, where he died. Simultaneously the Phœnicians began to search the western world for the metal, and finally found it in Britain. When Cornish tin began to come into the market, the corner that Asia had for so many centuries had on tin was broken, the Malaysian mines fell rapidly into decadence, and the ancient value of silver in the east was resumed. Europe then had the advantage, but as its silver product was on the decline, its trade with India fell away, and the two far separated parts of the world almost forgot each other. Europe, now well supplied with tin and copper, devoted itself to strenuous war and destruction. A thousand years or so later, when the Roman Empire had passed its prime, new silver mines were found in central Europe, and trade with the east began to revive once more. Venice was then the commercial center of the world, and it nourished as long as the Austrian and German silver mines were in bonanza, and when the cream of these was skimmed it began to decline. From that day till the years when Spanish galleons began to bring in silver from the new world, times in Europe were hard, civilization languished, and humanity suffered. Historians call the period the "Dark Ages." History also records the wonderful change that took place when the Mexican and Peruvian silver mines began to pour their flood of treasure into Europe. There was a marvelous revival of industry and of the arts and sciences, and the greater part of it was directly due to the enormous coinage of Mexican silver dollars, and their wide distribution in trade. This coin for three centuries has had a larger circulation, and has become more extensively known than any other tangible product of the hand of man.

From the date of the discovery of America up to about the beginning of the last century, the source of the world's supply of silver was almost entirely the mines of Mexico and of the west coast of South America. The production in this period is estimated by statisticians at nearly 200,000 tons, and its value (then about $30,000 per ton), at $6,000,000,000. The bulk of this vast total went first to Europe, and more than half of it in the shape of coins of American mintage. The remainder went into European coinage and plate. In those days it was not generally known that American silver always carried more or less gold, or else the methods of parting the two metals was very imperfect. Whichever was the case it is a fact that all the coins made in that period carried from two to five per cent of the yellow metal, and if any quantity of them could be now bought up at the commodity price of silver it would be a most profitable operation to separate the associated gold. This great store of what was, in those days, a money metal of unlimited legal tender value, enabled the new world to buy what it needed of Europe, and permitted the latter to resume its trade with the far east. Thus the old story was repeated. The pioneer, going westward, sends home the wealth he acquires through tremendous hardships, and upon this those who stay behind live luxuriously, or at least comfortably, as long as the good times last. And Spain, who was practically the parent and owner of those parts of the new world whence the metal came, prospered prodigiously, and became the wealthiest of the nations. But in 1810 its much-robbed and over-patient colonies began their struggle for independence. Spain resisted strenuously, and beggared herself in the effort to retain them. One by one, however, they tore themselves loose from her rule. The contest lasted through more than a decade,and during it the silver-mining industry suffered greatly. In South America it was almost suspended. The supply of the metal in Europe for coinage became scant, and trade with the orient again declined. In the middle of this period, when the destructive career of Napoleon was coming to an end, when all Europe was in financial distress, and vast amounts of plate had gone to the melting pot to be transformed into coin, with silver advancing in value (in terms of gold) until it commanded the equivalent of $1.40 to to $1.45 per fine ounce, with existing coinage of some of the nations in process of debasement by the addition of lead and tin to the alloy, England, in 1816, went on the mono-metallic gold basis, and started the train of conditions that later (in 1873) resulted in the complete demonitization of the white metal. And in this connection it is a most curious fact of history that while England in 1816 abandoned silver as a money metal because of its scarcity and high relative value in terms of gold, the rest of the great commercial nations followed her footsteps nearly fifty years later because of its abundance and falling value.

During the long struggle between Spain and her colonies the mining industry of Mexico was also greatly injured. When the country became independent in 1821 it passed into a condition of anarchy that lasted almost a half century. In this period its mines were operated under the greatest disadvantages, and the amounts of the metal exported was comparatively small. But as soon as political affairs in the republic became settled by the accession of President Diaz to power, the mining industry immediately began to revive, and to-day its output of the white metal exceeds that of any other nation.

Previous to 1859, when silver was first discovered in the United States (in Nevada), silver mining was not an organized industry in any sense of the word, but an occupation dependent largely for success upon the accidental discovery of bonanzas of very rich ore, and the ability to secure labor upon a basis of practical slavery. The Mexican and South American mines were worked by natives who were clothed, fed and sheltered merely to a sufficient extent to keep them alive during the prime of their physical powers. Only one step on the road of progress had been taken in the metallurgy of the metal, namely, the invention of what is known as the "patio process," which depended for its success largely on the element of unlimited time for its operation, coupled with nearly costless animal power. But when it became evident that the Comstock Lode in Nevada contained vast quantities of silver, the natural ingenuity and aptitude of the American transformed mining into a commercial industry, and the metal began to pour in such torrents into the money centers of the world that financiers became alarmed, and between 1870 and 1873 full coinage rights were finally denied by the principal nations. Meantime, a remarkable industry had come into existence in the mountain regions of our west. Thousands of silver mines had been discovered, scores of processes invented and put into practise for the treatment of their ores, and a vast number of metalliferous deposits developed that have since been yielding copper, lead, zinc, iron and manganese in addition to the white metal.

Silver occurs in veins or deposits in the rocky crust of the earth, and is never found in the gravel of stream beds as is gold. In a small number of cases the gangue, or material with which the metal is associated, is quartz alone, but generally one or more of the base metals is present, predominating vastly in quantity, and often in value. This is especially true after a little depth is gained on the veins, so that in due time mines that were opened as straight silver deposits became rather deposits of the other metals, the silver being practically a by-product. A good example of this change is to be found in the lodes of Butte, Montana. The veins at Parral, Pachuca and Guanajuato in Mexico are samples of straight silver mines, yet all of them are showing more or less associated iron or copper as depth is gained. On the other hand, wherever lead is found, silver is always present in some quantity, and, at the Comstock as well as at the Mexican districts just mentioned, there is invariably a proportion of gold. In the Comstock bullion it amounted to 40 per cent, of the total values. Thus the metallurgy of silver ores is not a simple matter, and in the days between 1860 and 1873, when the metal had a value of about $1.30 per ounce, a vast amount of study and experiment was devoted to the question of recovering it from its ores by milling processes, or methods not involving the fusion of the minerals. Preliminary roasting (sometimes in the presence of salt), followed by long-continued grinding with mercury, under water, was the system adopted in the majority of cases, the result being an amalgam of mercury and silver. This was then heated in retorts to volatilize the mercury, and the silver left behind was melted and cast into bars for shipment to market. Other processes involved the use of chemicals by the aid of which the metal was brought into a state of solution, and from which it was recovered by some method of precipitation. But as the west became opened by railroads so that ores could be cheaply transported to natural centers where coal or water power existed and labor was abundant and inexpensive, most of these processes were abandoned in favor of smelting, in which the ores, properly mixed to secure fusion, are melted in a blast furnace. The products are either copper or lead bars—according to the system used—and during the melt the precious metals unite with the baser ones, from which they are subsequently separated by electrolysis. In consequence of all this the production of silver may now be considered as a settled industry, and because the metal is now produced very largely as a by-product.

Since its discovery in the United States, and the application of business methods to the mining of its ores and their treatment, the world's output has amounted to nearly 170,000 tons. There has been nothing comparable to this enormous yield in any previous era of its history, and its fall in value may be considered as warranted, and perhaps permanent. The annual output of the world at the present time averages about 6,000 tons, and is not at all likely to seriously decline. The American and Mexican mines show no signs of exhaustion. On the contrary, new ones are continually being found. Asia and Europe are not likely to become large producers of the metal. The settled parts of the old world have been fairly well explored, and in the unsettled parts like Siberia, Turkey and Africa the mining laws are so burdensome that the prospector and individual miner (who are the advance guard in the exploration of the mineral resources of a land) will have nothing to do with those regions. In Australia somewhat similar conditions prevail. We may, however, confidently look to South America for many new and great silver mines, when the political situation becomes as stable as in Mexico, for Spanish mining law has always recognized the necessity of the prospector at the base of the industry. The extent to which the American crop of silver is a byproduct is shown by the following table worked out by the author for the year 1899, when the product of our mines amounted to about 2,100 tons.

Tons Per Cent.
Produced in connection with lead ores 750.75 35.75
Produced in connection with copper ores 514.50 24.50
Produced in connection with gold 504.00 24.00
Produced in connection with iron and manganese 173.25 8.25
Produced from straight ores 157.50 7.50

In Mexico, on account of the activity in Parral, Pachuca and Guanajuato, the proportion of silver coming from straight ores is larger, and perhaps the same is true for South America. But in Europe, Asia and Africa practically the entire product of silver comes from the distinctively lead and copper mines, so that for the entire world the proportions quoted in the above table would be about correct.

The demand for the metal is growing and may be expected to increase markedly in the near future. The largest consumers now, as in the past, are the three great backward races of the far east, the Hindus the Malays and the Chinese. It takes from 2,500 to 3,000 tons every year at present to maintain trade with them, and but one, the people of Hindustan and Farther India, may be said to have been more than wakened from their sleep of centuries. These number about three hundred millions of frugal, industrious and acquisative people. When the four hundred million of Chinamen are thoroughly aroused, and the one hundred million of mixed races that include the Filipinos and the inhabitants of the East Indian Islands, there will come at least as large a call for the metal as that which now exists. For silver is the only money that the orient recognizes, or can use. The capacity of that part of the world for absorbing it has always been the wonder of economists, to whom Asia is known as "the sink of silver" Statistics show that an average of not less than 600 tons of the metal has been sent to the east by Europe annually during the last 300 years. Practically none of it has ever come back. Among the thousand million Asiatics it has disappeared as hoards of coin, or bars, or as ornaments, or is afloat as money. This curious process is in progress to-day with nearly fivefold the vigor of the past. Practically seventy per cent, of all the silver produced in Europe and America since the dawn of history is now in the possession of the Chinese, Japanese, Malays and Hindus. Yet we regard them as a poverty-stricken people, which in fact they are, for with all this immense hoard of what was once the paramount money metal of the world, famine or pestilence is abroad nearly every year in one or more parts of the orient. This vast metallic accumulation will not save them when crops fail and starvation is at hand, for the west, having demonetized silver will not accept it in exchange for food except on the basis of a pure commodity.

From 400 to 500 tons of the metal is at present being consumed by the world in manufactures and the arts. Such parts as are used in photography and by the chemist may be regarded as lost, and it amounts to as much as 50 tons per year. The balance becomes table ware, jewelry and ornaments. About 5,000 tons goes into coinage. Fifty per cent, of this is minted in Asia, approximately twenty-five per cent, in Europe, fifteen per cent, in Mexico and South America and the balance in the United States. All this, except the coinage of India,. Mexico and Japan, is bought by the various governments at the commodity value of the metal, and after taking the stamp of the mint goes out to the public on the basis of the old ratio of 16 to 1 as compared with gold. The difference is absorbed as profit, under the name of seignorage. This profit to the treasuries of the civilized nations is now amounting to something more than $10,000,000 per annum, and is somewhat of the nature of a fraud on the people, though with the existing conventions in the matter of money and coinage it is not easy to say how the fraud can be avoided.

Considered wholly by itself, and from the standpoint of its purely physical properties, silver is yet a precious metal. Its pure white color and soft luster can not be approached in aluminum, tin, nickel or any other metal, and though it tarnishes quickly, and has not the resistant qualities of gold to the action of acids and of sulphur, yet no metal we at present know of can take its place for small coinage, or for ordinary table ware and decorative purposes. Aside from these uses it is the best conductor of electricity of all known substances, and there may be a special future for it in the wonderful-development of that new servant of man. Perhaps as the science of wireless telegraphy and telephony advances silver may come to be employed in the reproduction of sound waves when great distances must be bridged, or extreme delicacy of enunciation is desired. Yet copper approaches it so closely in electric sensitiveness, and is so much more abundant, and consequently cheaper, that we are not likely to do much of our talking in the future over silver wires.

The world's crop of silver during the } r ear 1907 amounted to about 0,400 tons, and came from the following parts of the globe in about the quantities given:

Tons Tons
Mexico 2,300 Europe 760
United States 1,900 Australasia 440
South America 420 Japan 120
Canada 400 China and Malaysia 15
Central America 30 Africa 10

From these figures it appears that nearly 80 per cent, of the annual product is coming from the western hemisphere, and if we add to this the output of Australasia, the proportion coming from what may he regarded as the newer parts of the world, so far as the question of its civilization is concerned, rises to 85 per cent. Finally, by including the European product, it will appear that Asia, where the metal is most in demand, and where it still retains all of its old debt-paying quality, produces less than 3 per cent, of the total world's crop. Hence there is still a large field for silver in the orient, and its exploitation and development is undoubtedly the next great task of the Caucasian. And in this view the silver miner may take some comfort.