Placer mining

“ The principal minerals, in order of value of output, are gold, copper, coal, lead and silver. Between 1858—the year of the placer discoveries on the Fraser river and in the Cariboo district—and 1882, the placer yields were much heavier than in subsequent years, running from one to nearly four million dollars annually, but there was no quartz mining. Since 1899 placer mining has increased considerably, although the greater part of the return has been from lode mining. ”

“ The gold yield will undoubtedly continue to fall, but to what point and at what rate no one can know. I believe that in 1870, the yield will not exceed thirty millions of dollars.
Placer Mines.—Placer mines are divided into many classifications. The first and most important is into deep and shallow. In the former the pay-dirt is found deep, twenty feet or more beneath the surface; in the latter, near the surface. The shallow or surface diggings are chiefly found in the beds of ravines and gullies, in the bars of rivers, and in shallow flats; the deep diggings are in hills and deep flats. ”

“ It exists no more. All mine development work ceased long ago. There are green-stained carbonates on the surface, but there are no copper ore-bodies. The "mines" have been dismantled of their machinery and other equipment, and not even a lone watchman remains to point out to the desert-wayfarer the spot on which was reared the monumental mining-stock swindle of the century. Every dollar invested by the public is lost. ”

“ Large areas, although so popular in England, do not compensate for large bodies of payable ore; the most remunerative mine is generally one of comparatively small area, but containing a large lode formation of payable, but often low grade, ore.
It is worse still, of course, to buy a practically worked out mine, though this too is sometimes done. It must be remembered that mining, though often so profitable, is nevertheless a destructive industry, thus differing from agriculture, which is productive, and manufactures, which are constructive. ”

“ These deposits are naturally the first to fail in productiveness, but the neighboring hills are formed of a gold-bearing quartz which is being crushed, night and day, by hundreds of powerful machines; and the works still pay ten thousand miners fair day-wages, besides giving the organized companies who employ them satisfactory dividends. Thus mining has been largely robbed of its adventurous character in this neighborhood, and perhaps also of most of its alluring charm, having become a sort of regular industry, like coal-mining, or even brick-making. ”

“ From all of which it will be seen that nearly $4,000,000 may be given as the product of the mines up to May, 1870.
Nor are the mines, as a whole, decreasing in value. The promise of the past is the promise of the future. If results ave been encouraging, they may be fabulous. There are fields above and below unoccupied. It needs, simply, that capital, energy, and practical mining experience combine, to make this second to no hydraulic region in the State. The wealth is here, and it remains to be seen whether the forces that produce it are to bless with their coming and successful working. ”

“ The miners do not support the earth by timber or pillars, as they should; the result is that the whole plot of about two hundred acres is gradually sinking, and this will eventually ruin the industry in that part of the deposit. In another part of the same field, a French company has purchased forty acres, and it is mining the whole tract and hoisting through one shaft by steam power. In that shaft they have sunk to a depth of six hundred feet, and are troubled with water and petroleum. These they pump out very much the same way as in coal and other mines, worked in a scientific manner. ”

“ The want of capitalists in the mine country, and of practical skill in the boring, blasting, sinking shafts and galleries, oppose obstacles to the [Pg 160] successful progress of mining. There is but one regular hearth-furnace for smelting in the whole district; and that is on the modern plan of English furnaces. There are not over four or five regular shafts in about forty mines; there is not an engine, either by horse, steam, or water power, for removing water from the mines, several of which have been abandoned on this account, with rich prospects of ore in view. ”

“ No one can appreciate the magnitude of those various movements by a simple perusal of statistics of the mineral wealth which they disclosed. He must pass through the mining belts and note how almost every rod of ground, over vast tracts of country, is filled with prospect holes that attest the miner’s former presence. If the trapper carried the tools of his trade to haunts remote and inaccessible, the miner, with his pick and shovel, certainly outdid him. ”

“ Such companies, with superior mechanical facilities to do much labor, in a short space, will be enabled to go over the whole mineral field, although already dug over by individuals, and reap yet a rich reward of their efforts. And when there will be no more gold washing to be done, then a new era in the mining of the country will commence—we mean a regular system of mining by sinking shafts into the very bowels of the rocks will be entered upon. ”

“ In irregular and uncertain deposits this work of development should be kept at all times so far in advance of mining operations as to ensure a regular and uniform output. In some cases, where the barren areas are large, it may be necessary to have two or three years’ supply of ore thus blocked out in advance. A mine, however, may be over-developed, which results in loss of interest on the capital unnecessarily locked up for years by excessive development, and involves additional cost for the maintenance of such openings until they are needed for active mining operations. ”

“ Upon the bed-rock is a deposit, from three to four feet in depth, of gravel and boulders, in which the gold is hidden. This is called by the miners "pay-dirt," and to remove it to the surface and wash it is the end of mining. It is an expensive and laborious process indeed. The water has first to be controlled; and in mines of not too great depth this is done by a drain ditch along the bed-rock, commenced many claims below. In this all the claim-holders are interested, and all contribute their quota of the labor and expense of digging it. ”

“ A deep old mine which has been abandoned, is undertaken with a chance of less profit and a certainty of greater risk, than a new and promising discovery. In the first case encouragement is often held out, by fixing very moderate dues, while in the other, so much is too frequently demanded and given, as to prevent that share of profit accruing to the adventurers which is due to the great risk constantly attendant on all mining pursuits. ”

“ Many gold mines have been abandoned as unprofitable that could have been mined at a profit had their owners been wealthy and enterprising enough to do a great deal of expensive prospecting by diamond drill, cross cuts, drifts and rises. In one instance that came to the writer's knowledge a clever mining engineer cleared nearly $200,000 profit by leasing for a term of years a gold mine that was supposed to be exhausted. A drill hole sunk less than 50 feet below the old workings revealed a pocket of ore in the vein, and paying quartz was found for many hundred feet below. ”

“ The price of gold, which is itself the standard of value, could not rise to offset growing mining costs and to maintain profits, as was the case with iron, copper, and the other metals,—with the result that the margin of profit in gold mining became so small as materially to affect exploration and production. Another important cause of decreased production was the actual exhaustion of certain mines, and the lowering of the grades of ore available in many others. ”

“ The holder of a miner’s right is entitled to enter upon any Crown land for the purpose of prospecting and searching for gold, and to take and maintain possession of a parcel or parcels of land and work the same, subject to the regulations and provisions of the Act; he is also authorised to cut timber for removal or for the erection of a place of residence or of business, and with the Warden’s consent, to make tramways or roads for mining purposes. Claims are of four kinds—alluvial deposits and river or creek beds; quartz lodes, reefs, and leaders ”

“ It is to the public interest that deposits of mineral should not be permitted to remain idle and undeveloped. This has been recognized from the earliest times, and laws have been framed in all countries for the encouragement of mining enterprise. In many cases the state or the ruler has sought to obtain a share in the profits of mining, or even to work mines for the individual profit of the ruler or of the state. ”

“ Upon the Rand, South Africa, a territory dominated by Englishmen, every mine is equipped with its own mill, and all notions of mining cover the inseparable idea of local ore treatment. Here, in our country, there are many, many mines which have absolutely no means of treating their own products and the managers give no thought whatever to metallurgical or milling lines. There are, on the other hand, many companies that have erected private plants at their mines for the extraction of metallic contents from the ores. ”

“ Under ordinary working conditions, it should be considered just as essential for a mine to take an occasional inventory as it is for a mercantile establishment. In truth, there is far more need in mining operations of the knowledge thus derived than in any other business. In mining, as already suggested, the business is one of selling off the stock in trade without replenishing it. The opening of more reserves of ore is not bringing more goods into the stock, but it may be likened to simply unpacking more goods in the storehouse. ”

“ The ore as taken from the mine concentrates four tons into one, which has a gross value of one hundred dollars, and with the first concentrator, whose capacity was one hundred and twenty tons daily, returned three thousand dollars per day to the owners. The company employ one hundred and fifty men, and are well equipped for profitable mining. ”

“ After a mine is once opened and preparations have all been perfected to operate [106] upon a certain scale of output, it is quite essential that exploitation and production be maintained without material fluctuations, if the greatest economy is to be attained. Exploitation, i.e., development work, must be kept well in advance of actual mining operations to assure plenty of working space for the extraction of the normal output. ”

“ But then, again, it is becoming plain to many experts in mining that, in working downwards from the surface itself, the future of their industry offers a wide field for the extension of the open-cut system. In proportion as power becomes cheaper, the expense attendant upon the removal of clay, sand, and rock for the purpose of laying bare the cap of a lode at a moderate depth becomes less formidable when balanced against the economy introduced by methods which admit of the miner working in the open air, although at the bottom of a kind of deep quarry. ”

“ All the world over, the operation of winning from the soil and rendering marketable the many valuable ores and mine products which abound is daily becoming more and more a scientific business which cannot be too carefully entered into or too skilfully conducted. The days of the dolly and windlass, of the puddler, cradle, and tin dish, are rapidly receding; and mining, either in lode or alluvial working, is being more generally recognised as one of the exact sciences. In the past, mining has been carried on in a very haphazard fashion, to which much of its non-success may be attributed. ”

“ Due consideration must always be given to the selection of some method of opening up what might be supposed will never amount to a great mine, so that, should subsequent disclosures exceed expectations, enlargement of the scale of operations can be advantageously effected. Always bear in mind that legitimate mining is just as much a commercial enterprise as is any other kind of business. The utmost concern for financial showings must be constantly borne in mind. Select a scale of operations consistent with the known—not the hoped-for—bodies of coal or ore ”

“ Moro, are perfectly competent to carry through the undertaking in which they have engaged, provided they are supported by the Shareholders at home; and every one at all acquainted with mining must perceive the immense advantages which would result from it to the Adventurers, as, in all their principal mines, it would ensure both the drainage, and the extraction of Ores, for the space of 132 yards of virgin ground, without the expence of machinery above ”

“ Some mines cannot be economically operated without the treatment of the ores upon, or close to, the mining property. With certain sorts of low-grade ore, or with those kinds of ores that may be concentrated before shipment, provision should be early made for the erection of appropriately designed mills. We say the subject should be considered early, but we do not advocate the premature erection of any mill. ”

“ They work badly; they cramp your energies; they entangle all your operations. In the mines, it will always be necessary for you to associate yourself with one or two, and sometimes with twenty, or even fifty mining companions. These associations are formed and terminate with the necessity of the occasion.
Much time is lost in the mines by those who are led, by exaggerated stories of success, from a place where they are working with some advantage, to seek a better location. ”