Abbildungen der Seite
PDF
EPUB

2. Report of the Chief Gold-Commissioner for the Province of Nova Scotia for the Year 1862. Made to the Honorable the Provincial Secretary, and dated at Halifax, January 23, 1863.

3. Report of the Provincial Geologist, Mr. Campbell Made to the Honorable Joseph Howe, Provincial Secretary, at Halifax, N. S., 25th February, 1863. Accompanied by a Section across the Goldbearing Rocks of the Atlantic Coast of Nova Scotia.

4. Report on the Gold-Districts of the Province of Nova Scotia. Made to the President and Directors of the Oldham Gold-Mining Company, December 28, 1863, by George L Chace, Professor of Chemistry in Brown University, Providence, R. I. Manuscript.

5. Introductory Remarks on the GoldRegion of Nova Scotia. Prefixed to a Report made to the President and Directors of the Atlantic Mining Company, December 31, 1863. By Benjamin Silliman, Jr., Professor of General and Applied Chemistry in Yale College, New Haven, Ct. Manuscript.

6. Report on the Montague GoldField, near Halifax, N. S., by the Same, and on the Gold-Fields of the Waverley District, by the Same. Manuscript.

7. Quarterly Report of the Chief GoldCommissioner of the Province of Nova Scotia. Made to the Provincial Secretary at Halifax, October 1, 1863.

8. The Royal Gazette, issued by the Chief Gold-Commissioner, Halifax, January 20, 1863. Published by Authority.

In confirmation of these documents, we shall only need to add the "testimony of the rocks" themselves, as shown in more than sixty specimens of the goldbearing quartz of these remarkable mines. Some of these were brought to Boston by Professors Chace and Silliman, on their return a few weeks since from exploring the rich leads of the Provinces, — but by far the larger number were forwarded by some of the resident superintendents of the mines, by the Cunard steamer Africa, arriving in Boston, Sunday, January

10, 1864, to the care of Captain Field, then residing at the Tremont House. We may add that the eight finest of these specimens are now lying on the table before us, their mottled sides thickly crusted with arsenical pyrites and streaked through and through with veins and splashes of twenty-two-carat gold. Incredulity, when raised to its highest pitch, might perhaps discredit all written testimony, whether official or scientific; but we have as yet seen no case so confirmed that the sight of these extraordinary fragments did not compel belief.

In drawing our narrative from the authorities above cited, we shall prefer to follow as closely as possible the precise statements of the documents themselves, — interspersed only with such remarks of our own as may be necessary best to preserve an intelligible connection between the different portions. The agreement between all the authorities is so substantial, and in fact entire, that we shall experience none of the usual difficulties in the reconciling of contradictions or the balancing of conflicting theories or statements.

The gold-fields of Nova Scotia consist of some ten or twelve districts of quite limited area in themselves, but lying scattered along almost the whole southeastern coast of the Province. The whole of this coast, from Cape Sable on the west to Cape Canso on the east, a distance of about two hundred and fifty miles, is bordered by a fringe of hard, slaty rocks, — slate and sandstone in irregular alternations, — sometimes argillaceous, and occasionally granitic. These rocks, originally deposited on the grandest scale of Nature, are always, when stratified, found standing at a high angle, — sometimes almost vertical, — and with a course, in the main, very nearly due east and west. They seldom rise to any great elevation, — the promontory of Aspatogon, about five hundred feet high, being the highest land on the Atlantic coast of the Province. The general aspect of the shore is low, rocky, and desolate, strewn often with huge boulde-rs of granite or quartzite, — and where not bleak and rocky, it is covered with thick forests of spruce and white birch.

The picture is not enticing, — but this is, nevertheless, the true arida nutrix of the splendid masses before us. The zone of metamorphic rocks which lines this inhospitable coast varies in width from six or eight miles at its eastern extremity to forty or fifty at its widest points, — presenting in its northern boundary only a rude parallelism with its southern margin,—and comprising, over about six thousand square miles of surface, the general outline of what may, geologically speaking, be called the Gold-Region of Nova Scotia.

It will be most interesting hereafter to mark the gradual changes already beginning to take place in this rich, but limited district. It is destined throughout, we may be sure, to very thorough and systematic exploration. For, although it is true that gold is not to be found in all parts of it, still it is not unreasonable to search for the precious metal throughout this whole region, wherever the occurrence of true quartz veins — the almost sole matrix of the gold — is shown by boulders on the surface. Back from the coast-line, a large part of the district named is now little better than an unexplored wilderness; and the fact that the remarkable discoveries which have been made are in a majority of cases almost on the sea-shore, and where the country is open and the search easy, by no means diminishes the probabilities that continued exploration in the less frequented parts of the district will be rewarded with new discoveries as important as any which have yet been made.

The earliest discovery of gold in tho Province, yet made known to the public, occurred during the summer of 1860, at a spot about twelve miles north from the head of Tangier Harbor, on the northeast branch of the Tangier River,—shown on McKinley's excellent map of Nova Scotia as about fifty-eight miles east from Halifax. Subsequent discoveries at Wine

Harbor, Sherbrooke, Ovens, Oldham, Waverley, Hammond's Plains, and at Lake Loon,—a small lake only five miles distant from Halifax, — have fully determined the auriferous character of particular and defined localities throughout the district already described, and abundantly justify the early opinion of Lord Mulgrave, that " there is now little or no doubt that this Colony will soon rank as one of the gold-producing countries of the world."

As a specimen of one of the most interesting mineral veins of this region, it may answer to select the Montague lode at Lake Loon for a specific description. The course of this vein is E. 10° N., that being the strike of the rocks by the compass in that particular district. It has been traced by surface - digging a long distance, — not less, probably, than half a mile. At one point on this line there is a shift or fault in the rocks which has heaved the most productive portion of the vein about thirty-five feet to the north; but for the rest of the distance, so far as yet open, the whole lead remains true and undisturbed.

Its dip, with the rocks around it, is almost vertical, — say from 85° to 80° south. The vein is contained between walls of slate on both sidea, and is a double or composite vein, being formed, 1st, of the main leader; 2d, of a smaller vein on the other side, with a thin slate partition - wall between the two; and, Sd, of a strongly mineralized slate foot-wall, which is in itself really a most valuable portion of the ore-channel.

The quartz which composes these interposed sheets, thus separated, yet combined, is crystallized throughout, and highly mineralized, — belonging, in fact, to the first class of quartz lodes recognized in all the general descriptions of the veins of this region. The associated minerals are, here, cuprite or yellow copper, green malachite or carbonate of copper, nuxpickel or arsenical pyrites, zinc blende, sesquioxyde of iron, rich in gold, and also frequent "sights" or visible masses of gold itoelf. The gold is also often visible to the naked eye in all the associated minerals, and particularly in the niispickel and blende.

The main quartz vein of this intereating lead varies from three to ten inches in thickness at different points on the surface-level, but is reported as increasing to twenty inches thick at the bottom of the shaft, already carried down to a depth of forty feet. This very considerable variation in thickness will be found to be owing to the folds or plications of the vein, to which we shall hereafter make more particular allurion.

The minerals associated with the quartz in this vein, especially the cuprite and mispickel, are found most abundantly upon the foot-wall side, or underside of the quartz itself. The smaller accompanying vein before alluded to appears to be but a repetition of the larger one in all its essential characteristies, and is believed by the scientific examiners to be fully as well charged with gold. That this is likely to come up to a very remarkable standard of productiveness, perhaps more so than any known vein in the world, is to be inferred from the official statement in the "Royal Gazette" of Wednesday, January 20,1864, published by authority,. at the Chief Gold - Commissioner's office in Halifax, in which the average yield of the Montague vein for the month of October, 1863, is given as 3 oz. 8 dwt. 4 gr., for November as 3 oz. 10 dwt. 13 gr., and for December as 5 oz. 9 dwt. 8 gr., to the ton of quartz crushed during those months respectively. Nor is the quartz of this vein the only trustworthy source of yield. The underlying slate is filled with bunches of mispickel, not distributed in a sheet, or in any particular order, so far as yet observed, but developed throughout the slate, and varying in size from that of small nuts to many pounds in weight, masses of over fifty pounds having been frequently taken out. This peculiar mineral has always proved highly auriferous in this locality, and a careful search will rarely fail to detect

"sights" of the precious metal imbedded in its folds, or lying hidden between its crystalline plates.

Nor is the surrounding mass of slate in which this vein is inclosed without abundant evidences of a highly auriferous character. Scales of gold are everywhere to be seen between its laminae, and, when removed and subjected to the processes of "dressing," there can be little doubt of its also yielding a very handsome return. In fact, the entire mass of material which is known to be auriferous is not less than twelve to fifteen inches at the surface, and will doubtless be found, as all experience and analogy in the district have hitherto shown to be the case, to increase very considerably with the increased depth to which the shafts will soon be carried. No difficulties whatever are apprehended here in going to a very considerable depth, as the slate is not hard, and easily permits the miner in his progress to bear in upon it without drilling upon the closer and more tenacious quartz.

The open cut, made by the original owners of the Montague property, and by which the veins have been in some degree exposed, absurd and culpable as it is as a mode of mining, has yet served a good purpose in showing in a very distinct manner the structure of these veins, — a structure which is found to be on the whole very general in the Province. The quartz is not found, as might naturally be supposed from its position among sedimentary rocks, lying in anything like a plain, even sheet of equal thickness. On the contrary, it is seen to be marked by folds or plications, occurring at tolerably regular intervals, and crossing the vein at an angle of 40° or 45° to the west. Similar folds may be produced in a sheet which is hung on a line and then drawn at one of the lower corners. The cross-section of the vein is thus made to resemble somewhat the appearance of a chain of long links, the rolls or swells alternating with plain spaces through its whole extent. Perhaps a better comparison is that of ripples or gentle waves, as seen following each other on the ebbtide in a still time, on the beach.

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 stalement that the gold abounds most at the swells, or highest points of the waves of rock, and that the scarcely less valuable mispiokel 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 goldregion 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 Kova 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," — be must, we think, mean to its fullest extent, since he adds immediately after, that, •' aa 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 Scoria. 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 southeast 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, Sherbrookc, 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 tie 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 twentyfive 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 GoldCommissioner 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 mis

conception 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 GoldCommissioner 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 CustomHouse 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

« ZurückWeiter »