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Exports of copper ores from San Francisco from January, 1862, to October, 1866.

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The above table includes concentrated ores and regulus, when shipped in bags or barrels, but not metallic copper in pigs or bars, of which there was shipped about 25 tons in 1865 and 3,787 bars, of unknown weight, in 1866. In this quantity is included 120 tons from the smelting works at Buchanan Hollow, Mariposa county, shipped by Coffee & Risdon, of San Francisco. As this metal averages 80 per cent., one ton of it is equal to five tons of 16 per cent. ore. The export of this metal is consequently equal to 1,725 tons of such ore, making a total, when added to quantity in the first table, of 79,964 tons-in round numbers, say 80,000 tons; in addition to which there are upwards of 2,000 tons of ores at Stockton and San Francisco ready for shipment, awaiting vessels to carry it away, and nearly 20,000 tons are ready for shipment at the various mines, where it is retained in consequence of the very low price of such ores in this market at present; the whole showing that upwards of 100,000 tons of copper ore have been taken out of the mines of California since their discovery in 1860. Estimating this ore at an average value of $50 per ton, which is very much below its actual value, the products of these copper mines since their discovery have added $5,000,000 to the material wealth of the country, and opened a wide field for the employment of the enterprise, capital, and labor of thousands of its citizens. A comparison of the product of the copper mines of the Pacific coast with those in other countries may be instructive in this place. Sir Henry De La Beché, the head of the department of mines in England, stated in a lecture given at the great exhibition in London, in 1861, that the average of all the ores of copper produced in Cornwall and Devonshire did not exceed 8 per cent. when dressed, and that the supply was constantly becoming less, and more costly to obtain as the working in the mines became deeper. These two counties are the chief sources of copper in all Europe. Here, on this coast, there are absolutely inexhaustible sources of ores ranging from 10 per cent. to 12 per cent., which may be obtained within a couple of hundred feet of the surface of the ground.

In the parliamentary returns published by order of the British government, it appears that in the year 1861 the gross yield of copper ores in Great Britain, including England, Ireland, and Wales, amounted to 231,487 tons of the value of $6,800,000, or a little over $29 per ton. On this coast, under the present system, ore of that value would not pay to take it out of the ground. As has already been explained it costs between $40 and $50 per ton to place the ores obtained on this coast in a market. The rates for freight to New York and Liverpool are more than double as high as they were two years ago, in consequence of the great demand for first class vessels to carry grain to those places.

Concluding remarks.—None of the metallic copper made on this coast is suitable for castings or for rolling into sheets, owing to defects in the processes for refining it. It is too brittle for rolling, in consequence of containing traces of sulphur. It is too hard for casting, turning, and polishing, and too liable to tarnish and turn nearly black in color, in consequence of containing more or less iron in alloy.

The present depression in the copper mining interests on the Pacific coast has been much increased by the excessive cost of freight to New York and Swansea, which, falling at a time when the ores are of less value than they have been for the past fifteen or twenty years, causes it to be unprofitable to ship those that heretofore have formed the great bulk of the exports. The price of freight at this time is nearly double what it was in 1861 and 1862. To illustrate this fact, it may be stated that the ship Haze, in 1861, was chartered to carry a cargo to New York for $5,000 in gold. Within the past few weeks the same vessel has been chartered for the same destination for $16,660 in gold, or $25,000 in currency. In 1861 freight to Liverpool was offering at $11 per ton; at present it is not procurable at less than $17 per ton.

It will be readily understood that an article, the exports of which, though amounting to two millions of dollars annually, the profits of which are limited to such a slight margin, as already explained is the case with copper ores on this coast, must cease to be a source of revenue to the government, or of employment and profit to the people, when the cost of its production and export exceeds the value of the product. This is a question deserving the most serious consideration.

The products of the copper mines on the Pacific coast might be greatly increased if the legislation of Congress were so framed as to make them profitable to procure. This would increase the taxable property of the country, while the products of the mines, now far below their capacity, would add materially to its absolute wealth; for if we do produce our own copper, it must be purchased from other nations, for money or produce, as it is indispensable in the arts and manufactures.

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Under our form of government, with such an extent of territory as we possess, and such an intelligent and enterprising people as inhabit our mineral regions, it should be a paramount object so to regulate the scale of taxes and duties on the products of any branch of national industry as to encourage the labor engaged in its development. A sound policy would dictate that so great an interest as copper mining is destined to become in the United States should be encouraged by every possible means in its infancy, and until the skill and experience of those interested in its development shall enable them to compete with a reasonable hope of success with the copper miners and smelters of other countries in which the business has been conducted for centuries. This they cannot do at present, nor ever will be able to do, unless they are assisted for a few years by favorable legislation. The duties and taxes, direct and indirect, on copper, under the present system, amount to $4 63 on each 100 lbs. of American-made metal, while that imported from other countries only pays $2 50 on each 100 lbs. It is this invidious distinction that is crippling the energies of those interested in developing the copper resources of the Pacific coast. A reversal of this state of affairs, the levying of a duty of about $250 on each 100 lbs. of foreign copper, over and above what is levied on our homeproduced copper-a duty that would inflict no injury on any American interestwould immediately revive the now languishing copper interests of the whole country.

Measured by the facts and figures contained in this report, it requires no stretch of the imagination to comprehend the great national importance of the copper resources of the Pacific coast; already, within five years of their discovery, exporting sufficient ores of unusual richness to produce 10,000 tons of metal annually—a quantity nearly equal to one-half of the supply of the whole world twenty-five years ago, and five times as large as the produce of the whole United States only ten years ago! It requires but experience and the advantages it gives, and a slight protection on the part of the general government, to make the Pacific coast occupy the same prominence as a copper-producing country that it now occupies as the producer of gold and silver.

SECTION 6.

QUICKSILVER MINES OF CALIFORNIA.

1. New Almaden mines.-2. Products and exports.

1.-NEW ALMADEN MINES.

The ore of quicksilver.-Cinnabar is the principal and only valuable ore of the mercury of commerce, which is prepared from it by sublimation.

It is a sulphide (sulphuret) of mercury, composed, when pure, of quicksilver 86.2, sulphur 13.8, in which case it is a natural vermilion, and identical with the vermilion of commerce; but it is sometimes rendered impure by an admixture of clay, bitumen, oxide of iron, &c. Cinnabar is of a cochineal red color, often inclining to brownish red and lead gray, with an adamantine lustre, approaching to metallic in dark varieties, and to dull in friable ones. It varies from subtransparent to opaque, has a scarlet streak, and breaks with a subconchoidal uneven fraction. H = 2 to 2.5, specific gravity 8.99. In a matrass it entirely sublimes, and with soda yields mercury with the evolution of sulphurous fumes. When crystallized it belongs to the rhombohedral system.

Cinnabar occurs in beds in slate rocks. The chief European beds are at Almaden, near Cordova, in Spain, and at Idria, in Upper Carinthia, where it usually occurs in a massive form, and is worked on a thick vein belonging to the Alpine carboniferous strata. It also occurs in China, Japan, Pluanca Vilica, in South Peru, and at New Almaden, in California, in a mountain east of San José, between the bay of Francisco and Monterey, where it is very abundant and easy of access. Ure's Dictionary.

Classes of cinnabar ores.-Gruesa is the best quality or first class, in pieces eight to twelve inches or more in diameter; mostly pure ore of cinnabar, with little or no admixture of refuse rock.

Granza is the second quality, in pieces of three to eight inches, generally containing a considerable proportion of rock. It is either taken from the mine in such pieces or is broken off from larger pieces of rock in the yard.

Tierras-earth or dirt-is the lowest quality, and is not taken into account in the ores produced at the mine; neither are the miners paid for it. It is made into bricks and sun-dried previous to being reduced in the furnaces. Each adobe or brick weighs about twelve and a half pounds.

The “carga" or load of ore is considered to be three hundred pounds.

Extracts of a report by Professor B. Silliman, jr., from the American Journal of Science and Arts for September, 1864.

The New Almaden quicksilver mines are situated on a range of hills subordinate to the main Coast range, the highest point of which at the place is twelve to fifteen hundred feet above the valley of San José. Southwest of the range which contains the quicksilver mines, the Coast range attains a considerable elevation, Mount Bache, its highest point, being over thirty-eight hundred feet in height.

New Almaden is approached by the railroad running from San Francisco to San José, a distance of forty-five miles. In the course of it there is a rise of one hundred feet, San José being of this elevation above the ocean. From San José to New Almaden the distance is thirteen miles, with a gradual rise of one hundred and fifty or perhaps two hundred feet.

The rocks forming the subordinate range, in which the quicksilver occurs, are chiefly magnesian schists, sometimes calcareous and rarely argillaceous. As a group they may be distinguished as steatitic, often passing into well-characterized serpentine. Their geological age is not very definitely ascertained, but

they are believed by the officers of the State geological survey to be not older than cretaceous. But few fragments of fossils, and these very obscure, have yet been found in these metamorphic rocks. At a point just above the dumps, behind the reduction works at the hacienda (or village,) there is an exposure, in which may be clearly seen in projecting lines the waving edges of contorted beds of steatite and serpentine, interspersed with ochrey or ferruginous layers, more easily decomposed; and the partial removal of the latter has left the steatitic beds very prominent.

The mine is open at various points upon this subordinate range over a distance of four or five miles, in a northeast direction. The principal and the earliest workings of the mine were in a right line, but little more than a mile distant from the hacienda. The workings are approached, however, by a wellgraded wagon road, skirting the edges of the hills, which is two and three eighths miles in length.

It appears, partly from tradition, and partly from the memory of persons now living, that the existence of cinnabar upon the hill was known for a long time prior to the discovery that it possessed any economic value. In fact, upon the very loftiest summit of this subordinate range, cinnabar came to the surface, and could be obtained by a slight excavation or even by breaking the rocks lying upon the surface. In looking about for physical evidences such as would aid the eyes of an experienced observer in detecting here the probable presence of valuable metallic deposits, one observes on the summit of the hill, at various points along the line of its axis for two or three miles, and also beyond, toward the place called Bull Run, occasional loose boulders of drusy quartz, with more or less well-characterized geodes and combs; accompanying which is an ochraceous or ferruginous deposit, such as frequently forms the outcrop of metallic veins. There is, however, no such thing as a well-characterized vein, the quartz and its associated metals occurring rather in isolated masses or bunches segregated out of the general mass of the metamorphic rocks, and connected with each other, if at all, somewhat obscurely by thread veins of the same mineral.

The main entrance to the mine at present is by a level about eight hundred feet long, and large enough to accommodate a full-sized railroad and cars. This level enters the hill about three hundred feet from its summit, and is driven into a large chamber, formed by the removal of a great mass of cinnabar, leaving ample space for the hoisting and ventilating apparatus employed in working

the mine.

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At this point a vertical shaft descends to an additional depth of nearly three hundred feet, over which is placed a steam "whim" with friction gearing and wire rope, worked by a steam-engine, and by means of which all the ore from the various workings of the mine is conveniently discharged from the cars, which convey it out of the level to the dressing floors. In order to reach the lower workings of the mine, the observer may employ the bucket as a means of descent, or he may, in a more satisfactory manner, descend by a series of ladders and step, not in the shaft, but piaced in various large and irregular openings, dipping for the most part in the direction of the magnetic north, and at an angle of thirty to thirty-five degrees. These cavities have been produced by the miner in extracting the metal, and are often of vast proportions; one of them measures one hundred and fifty feet in length, seventy feet in breadth, and forty feet in height; others are of smaller dimensions ; and they communicate with each other sometimes by narrow passages, and at others by arched galleries cut through the unproductive serpentine. Some portions of the mine are heavily timbered to sustain the roof from crushing, while in other places arches or columns are left in the rock for the same purpose.

The principal minerals associated with the cinnabar are quartz and calcareous

spar, which usually occur together in sheets or strings, and in a majority of cases penetrate or subdivide the masses of cinnabar. Sometimes narrow threads of these minerals, accompanied by a minute coloration of cinnabar, serve as the only guide to the miner in re-discovering the metal when it has been lost in a former working.

Veins or plates of white massive magnesian rock and sheets of yellow ochre also accompany the metal. Iron pyrites is rarely found, and no mispickel was detected in any portion of the mine; running mercury is also rarely, almost

neyer, seen.

The cinnabar occurs chiefly in two forms, a massive and a sub-crystalline. The first is fine granular, or pulverulent, soft, and easily reduced to the condition of vermillion; the other is hard, more distinctly crystalline, compact and difficult to break; but in neither of these forms does it show any tendency to develop well-formed crystals. It is occasionally seen veining the substance of greenish white or brown compact steatite or serpentine.

The ores are extracted by contract, the miners receiving a price dependent upon the greater or less facility with which the ore can be broken. By far the larger portion of the work-people in the mines are Mexicans, who are found to be more adventurous than Cornishmen, and willing oftentimes to undertake jobs which the latter have abandoned. The price paid for the harder ores in the poorer portions of the mine is from three to five dollars per carga of three hundred pounds. This weight is obtained after the ore is brought to the surface and freed by hand breaking from the superfluous or unproductive rock; by this arrangement, the company are secured from paying for anything but productive mineral. All the small stuff and dirt formed by the working of the labors," are also sent to the surface to form the adobes used in charging the furnaces.

It has often happened in the history of this mine, during the past fifteen years, that the mine for a time has appeared to be completely exhausted of ore. Such a condition of things has, however, always proved to be but temporary, and may always be avoided by well-directed and energetic exploration. Upon projecting, by a careful survey, irregular and apparently disconnected chambers of the mine in its former workings in a section, there is easily seen to be a general conformity in the line of direction and mode of occurrence of the productive ore-masses. These are found to dip in a direction toward the north, in a plain parallel, for the most part, to the pitch of the hill, but at a somewhat higher angle. An intelligent comprehension of this general mode of structure has always served hitherto in guiding the mining superintendent in the discovery of new deposits of ore.

Since the settlement of the famous lawsuit, which has so long held this company in a condition of doubt, the new parties, into whose hands the property has now passed, have commenced a series of energetic and well-directed explorations at various points upon the hill, with a view to the discovery of additional deposits of ore. At one of these new openings, distant at least five hundred feet from the limit of the old workings, and not more than two hundred feet from the summit of the hill, a deposit of the richest description of the softer kind of cinnabar has been discovered, which, so far as hitherto explored, has a linear extent of at least seventy or eighty feet, and in point of richness has never been surpassed by any similar discovery in the past history of the mine. A charge of one hundred and one thousand pounds, of which seventy thousand were composed of this rich ore, thirty-one thousand pounds of "granza" or ordinary ore, and forty-eight thousand pounds of adobes, worth four per cent., making a total charge of one hundred and five thousand eight hundred pounds, yielded, on the day of our visit, four hundred and sixty flasks of mercury at seventy-six and a half pounds to the flask. This yield is almost without parallel in the history of the mine. The only preparation which the ores un

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