The distribution of the gold in the mass of the quartz appears to be highly influenced by this peculiar wavy or folded structure. All the miners are agreed in the statement that the gold abounds most at the swells, or highest points of the waves of rock, and that the scarcely less valuable mispickel appears to follow the same law. The spaces between are not found to be so rich as these points of undulation; and this structure must explain the signal contrast in thickness and productiveness which is everywhere seen in sinking a shaft in this district. As the cutting passes through one of these original swells, the thickness of the vein at once increases, and again diminishes with equal certainty as the work proceeds,—below this point destined again to go through with similar alternations in its mass.
"There can be no fear, however," says Mr. Silliman, (Report, p. 10,) "that there will be any failure in depth" (i.e., at an increased depth of excavation) "on these veins, either in gold product or in strength. The formation of the country is on too grand a scale, geologically, to admit of a doubt on this point, so vital to mining success." Mr. Campbell, whose masterly survey and analysis of the whole gold-region forms, with the colored section accompanying it, the basis for a general and thorough understanding of the whole subject, adds (Report, p. 5) that "the yield per ton of such quartz when crushed cannot fail to prove highly satisfactory." And Mr. Chace, in the Preface to his Report on the Oldham District, (p. 6,) remarks, that, "if, as there are reasons for believing, the gold-bearing quartz of Nova Scotia is of sedimentary origin, in that case I see no reason why depth should cause any decline in the richness of the ore. As yet, none of the shafts have been carried down sufficiently far to test this question practically,"—he must, we think, mean to its fullest extent, since he adds immediately after, that, "as far as they have gone, the ore is very generally believed to have improved with increase of depth."
Such, then, is a brief and imperfect description of the general character of one of the representative veins or "leads" of the gold-fields of Nova Scotia. Of the extent and number of similar deposits it is scarcely possible at present to give any definite idea. The line along which Mr. Campbell's section is made out extends from the sea-shore at the south-east entrance of Halifax Harbor to the Renfrew Gold-Field, a distance a little over thirty miles to the northeast, intersecting in that distance no less than six great anticlinal folds. The points at which the east and west anticlinal lines are intersected by north and south lines of upheaval form the localities in which the quartzite group of gold-bearing rocks are brought to the surface, and it is here that their outcroppings form the surface of the country. The official "Gazette" for January, 1864, enumerates nine of these districts as already under a course of active exploration, namely, Stormont, Wine Harbor, Sherbrooke, Tangier, Montague, Waverley, Oldham, Renfrew, and Ovens. When we add, in the words of Mr. Silliman's second conclusion to his Report on the Atlantic Gold-Field at Tangier, "that the gold-bearing veins already explored on this estate alone are in number not less than thirty, and that there is every reason to expect more discoveries of importance, as the results of future explorations, already foreshadowed by facts which have been stated," enough, we think, will have been deduced, on the highest kind of scientific testimony, to bear out our opening statement, that there exist in Nova Scotia veins of auriferous quartz practically inexhaustible, by any known methods of mining, at least for the next two hundred years.
One very remarkable characteristic of all the gold hitherto produced in Nova Scotia is its exceeding purity, it being on the average twenty-two carats fine, as shown by repeated assay. In this respect it possesses an advantage of about twenty-five per cent. of superior fineness, and consequently of value, over most of the yield of California, much of which latter reaches a standard of only sixteen or seventeen carats' fineness, and is therefore inferior by five or six carats in twenty-four to the standard of the gold of Nova Scotia. The gold from all the districts named is sold commonly in Halifax in bars or ingots, at about $20 the ounce. Professor Silliman states the value of some of this gold, assayed under his direction at the Sheffield Laboratory in New Haven, Connecticut, at $19.97 per ounce, while the standard of another lot, from the Atlantic Mine in the Tangier District, is fixed by him as high as $20.25 per ounce. The Official Report of the Provincial Gold-Commissioner for the year 1862 assumes the sum of $19.50, Nova-Scotia currency, as the basis upon which his calculations of gold-value of the yield of all the mines is made up. A quantity of gold from the "Boston and Nova-Scotia" mines in the Waverley District, just coined into eagles at the United-States Mint, and the results of which process are officially returned to the President of that Company, required a considerable amount of alloy to the ore as received from the mines, in order to bring it down to the standard fineness of the United-States gold-currency. All the Nova-Scotia gold is uncommonly bright and beautiful to the eye, and it has often been remarked by jewellers and other experts to whom it has been shown, that it more nearly resembles the appearance of the gold of the old Venetian ducats—coined mostly, it is supposed, from the sands of Guinea—than any other bullion for many years brought into the gold-market.
In regard to the most important point of the whole subject, namely, the average yield per ton of quartz crushed at the various mills, we are fortunately enabled to give the official returns of the Deputy Gold-Commissioners for the several districts, as made to the Chief Commissioner at Halifax. A few words of explanation as to the definite and statistical character of these returns may be of value here, in order to prevent or to correct much misconception and want of knowledge with regard to their absolute reliability.
In the first place, then, every miner, or the agent or chief superintendent of each mine, is required by law to make a quarterly return of the amount of days' labor expended at his mine, the number of tons of quartz raised and crushed, and the quantity of gold obtained from the whole,—neglecting to do which, he forfeits his entire claim, and the Gold-Commissioner is then empowered to grant it to another purchaser.
These returns are therefore made with the utmost regularity and with the greatest care. But as the royalty of three per cent. to the Government is exacted on the amount of this return, whatever it may be, it is obvious that there exists no motive on the part of the miner to exaggerate the amount in making his statement. We may be as sure that his exhibit of the gold admitted to have been extracted by him does not, at any rate, exceed the amount obtained, as that the invoices of importations entered at the Custom-House in Boston do not overstate the value of the goods to which they refer. The practice is generally suspected, at least, to tend in quite the opposite direction.
As the next step for ascertaining the yield of the mines, there comes in a form of scrutiny which it would be still more difficult to evade. All owners of quartz-mills are also required to render official returns under oath, and in a form minutely prescribed by the Provincial law, of all quartz crushed by them during the month, stating particularly from what mine it was raised, for whose account it has been crushed, and what was the exact quantity in ounces, pennyweights, and grains. And this is designed also as a check on the miner, as the two statements, if correct, will be found, of course, to balance each other.
The Chief Gold-Commissioner resides in Halifax, and has his deputy in each gold-district, whose duty it is, as a sworn officer of the Government, to see that the provisions of the law are carried out; and the returns, as collected, are duly made by him each month, accompanied by a general report on the industrial condition of the district represented. It is from these returns, thus collected, that the Gold-Commissioner-in-Chief prepares a quarterly exhibit, which he issues on a broad sheet in a so-called "Royal Gazette." The last of these documents issued was published by authority at Halifax, Wednesday, January 20th, 1864, and a copy thereof, ornamented at the head with the familiar lion and unicorn, is now lying with several of its predecessors on the table before us. If skeptics desire any better authority than this for the average yield of these mines, they must seek it elsewhere for themselves. By the majority of persons capable of judging of the value and weight of testimony, we presume it will be regarded as amply sufficient.
After this explanation of the official character of these returns, a transcript of the figures given in the last exhibit as the average yield of gold per ton of quartz crushed will be all we think necessary in answer to the inquiry we have proposed. We give them just as they stand in the returns for December, 1863, only premising that the relative yield of the several mines is found to vary very considerably from month to month, being at one time higher, and at other times again somewhat lower, and this from natural causes which have already been explained, while the total amounts, when taken together, exhibit a steady increase in the general yield of the whole. The figures stand as follows:—