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By comparing these expenses with the list of prices above, it will readily be perceived that ores under 15 per cent. do not cover expenses. As seven-eighths of the ores obtained on this coast do not reach that standard, it is unprofitable to extract them. The same figures apply to the markets at New York and Boston. As more than three-fourths of the ores smelted in Europe and the Atlantic States do not average 15 per cent., it is clear that the mines whence such ore is obtained possess a great advantage over those on the Pacific coast, entirely through the saving in cost of labor and transportation.

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The statistics relating to the copper mines of England, published by authority of the government of that country in 1866, show that during that year 198,298 tons of ore were obtained from the English mines, which yielded 11,888 tons of fine copper, or an average of but 5.9 per cent. This ore, estimated at $25 per ton, was valued at $4,967,450. As the mines on this coast could be made to produce annually an equal quantity of ore of greater value, the proportions of the loss the country sustains by their remaining undeveloped deserves considera

tion.

The establishment of comprehensive smelting works at some suitable place, with ample capital to conduct operations on a liberal scale, would be a great advantage to the country by encouraging the development of this interest, and would doubtless in time yield fair returns for the amount invested.

The present plan of erecting temporary smelting works near each mine, for the purpose of operating on the richest ores, is an injury to the copper interest, because it exhausts materials which might be more advantageously employed. These temporary works can only operate on the richest oxides, carbonates, and silicates, which form but a small proportion of the ores. The great mass of them consists of sulphurets, in the reduction of which the oxygen, carbon, and silica of the richer ores serve an important purpose. It is the opportunity of selecting suitable ores for combining, which the smelters of Wales possess, with a market for every kind and grade offered, that enables them to operate so successfully. The ores from the Cornish mines are sulphides, and would be too poor to work, but for this arrangement. Lime and silica being essential elements in the reduction of copper from its ores, common sense teaches that it is more economical to employ these elements when combined by nature with the metal, than to collect them from other sources and mix them artificially, at additional cost. It was to secure this advantage that the Boston smelters, during the past year, sent to Wales to purchase a cargo of carbonates to mix the sulphides received from this coast, because the miners here, who have large quantities of carbonates, prefer converting them into matte.

None of the English copper miners ever smelt their ores. They are all sent to the public market; smelting and mining being considered separate and distinct operations in that country.

The method of transacting business in the Welsh ore market is peculiar, but gives satisfaction, owing to its fairness to buyer and seller. All the ores intended for sale are piled and sampled ten days before the sale takes place. During that time the smelters desiring to do so can take samples to estimate the value of such parcels as they want. Each sends in his bid in writing, sealed, directed to the agent having the particular parcel for sale. The highest bidder for, any lot has it awarded to him. This is a better plan than for miners to be obliged to seek purchasers, without knowing the value of the ore in the market.

NEW DISCOVERIES.-The circumstances above stated have had the effect of preventing prospecting for copper to a great extent. But some discoveries have been made within the present year, though few of them have been much developed. Among the most important are the following:

The Sierra Buttes copper mine, located near Hurd's ranch, Sierra county. The lode on this discovery, which may be traced by its outcrop for nearly a mile, differs from that in any of the copper mines, in several material respects. It is

the only body of copper ores of any importance thus far found in the granite on this coast, except at Meadow lake, Nevada county, hereafter referred to.

The ore is contained in a quartzose gangue rock, the lode having a well-defined fluccan (as the miners term the soft clay which usually accompanies true veins of ore) on the foot wall; the hanging wall being a hard, compact, feldspathic granite, which also constitutes the "country" in which the lode is enclosed. There are considerable quantites of molybdenum in the vein-stone, in the form of both the sulphite and oxide of that metal. There are other lodes of copper ores in the same locality contained in the granite; but each differs somewhat in composition and appearance from all the others, forming an interesting field for scientific investigation. The Sierra Buttes is the only one of these lodes that has been worked to any extent, owing to its containing sufficient gold in the gangue rock to pay for extraction, though the ore will average 10 per cent. of copper. The cost of transportation from that distance to a market over such roads as exist, under the present condition of affairs, causes such a grade of ores to be valueless. A tunnel is in course of construction on this mine, which when completed will strike the lode at a depth of 1,000 feet below the surface. In a shaft sunk on it to the depth of 60 feet, the lode was found to be seven feet wide.

A promising outcrop of copper ore has been found near Marango Pass, San Bernardino county, California.

A company was incorporated at San Francisco in July, 1867, with a capital stock of $240,000, for the purpose of working a copper mine in the Moro district, San Luis Obispo county, California.

In the California mine, at Meadow lake, Nevada county, the highest inhabited portion of the Sierra Nevada, at an altitude of 8,000 feet above the level of the sea, metallic copper is found in the quartz, the gold and copper in which, though intimately mixed, are never alloyed with each other.

The vein-stone of the lodes in this elevated district carries a percentage of copper, generally in the form of sulphurets, combined with those of iron, lead, zinc, cobalt, nickel, and arsenic. In the Shooting Star mine, at the depth of 40 feet, the lode contains an ore which yields 15 per cent. of copper, $40 per ton of silver, and $20 per ton of gold. It is proposed to erect furnaces to smelt the rich but complex ores of this district.

The Lyons Company's mine, located about three miles from the town of Ashton, Colusa county, in the Coast range, contains a body of oxides and carbonates. A temporary furnace was erected to work these ores, but being unfit for the purpose, one of Haskell's water-lined furnaces is now being built. This, though not a new discovery, had not been of much importance till smelting operations were commenced.

Persons who have visited the new Territory of Alaska report it as being rich in copper. M. Foucoult, a French gentleman, who spent several months in the Territory among the Indians, states that they value copper as much as civilized men value gold. The chiefs wear masses of it suspended round their necks, as highly prized ornaments. Some of the higher chiefs have lumps of the metal that weigh several hundred pounds each, which are heir-looms of the tribe, and are kept in the great wigwam. This gentleman states, that in order to obtain these nuggets of copper, the Indians keep up large fires for weeks on the outcroppings of the lodes, which melts the carbonates and oxides near the surface. It is a well-known fact, mentioned in the writings of the earlier visitors to this coast, that the natives of that Territory, and those immediately adjoining, were the only tribes that possessed copper weapons and ornaments when first discovered. In August, 1866, a discovery of copper ore was made in the mountains, on the south branch of King's river, Tulare county, about 68 miles from Fresno City. There are four distinct and parallel lodes, a few feet apart from each other, in the locality, each containing a percentage of "horseflesh" ore, or erubescite, in a quartzose gangue rock. The lodes are from two to eight feet

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wide, and are traceable for several miles, cresting a high hill and across a steep canon. An analysis of the ore shows it to contain 60 per cent. copper, $20 per ton in gold, and nearly $60 per ton in silver. Owing to the mountainous character of the country where this discovery was made, but little can be done towards its development till a road can be made to convey materials. This will involve an expense, which capitalists are not disposed to incur in prospecting copper mines at present. If there were no copper in the ledges, there would be less difficulty in obtaining funds to prospect them for the gold and silver they contain; but the disasters which have befallen the copper interest within the past year have cast a feeling of distrust over everything bearing the name or nature of copper. There is abundance of wood and water in the vicinity of the discovery; and could one of Haskell's furnaces be erected there, the parties who own the lodes would probably realize something for their labor and enterprise.

Several discoveries have been made within the past few months in the mountains bordering the Tule river, in Tulare county, which have been prospected sufficiently to demonstrate their value. The lodes are generally similar in character to those found on the south fork of King's river, in the same county, and described above. The localities of the two discoveries are about 50 miles apart. The lodes on the Tulare are contained in the metamorphic slate, near its junction with the granite.

A body of ore has been partially developed near Copper City, Shasta county, on which a company of English capitalists have offered to erect smelting works, provided the parties owning the mine will grant them a lease on terms they propose.

It is stated by parties who have been prospecting in Utah during the past season that the croppings of copper ore are abundant in the south and southeast sections of that Territory. Copper ores are reported to have been found in the Battle Mountain district, Humboldt county, Nevada, about 90 miles north-northwest from Austin.

The surveyors employed by the Central Pacific Railroad Company report the existence of copper-bearing lodes in the Trinity mountains, Humboldt county, Nevada.

RECENT DEVELOPMENT OF THE COPPER MINES.-The condition of affairs, resulting from the causes stated, will be best exhibited by showing the extent of the development of the mines described in the previous report. This will also afford a means for comparison.

THE COPPEROPOLIS MINES.-These mines, owing to their extent, the capital expended in their development, the value of the ores extracted from them, and the quantity at present available for extraction, place them at the head of the copper mines on the Pacific coast.

The Union mine has been but partially worked during 1867. Its owners find it more profitable to place it in a condition for future operations, than to extract ore for sale at present prices. But little ore has consequently been taken out-only such as it was necessary to move in making explorations. The number of men employed has been reduced to 150; in 1865 and 1866 nearly 400 were employed. The chief work doing at the mine at present is keeping it free from water and making the necessary repairs to the works above and below ground. The explorations in the main shaft have extended to 500 feet in perpendicular depth, where the lode on the north, near the line of the Keystone ground, is 15 feet wide. At the 400-feet level in the same shaft, 100 feet above, the lode has decreased to six feet in width. This increase in its proportions is a favorable symptom of permanence, and proves the correctness of the opinion that the contraction of the lode at the 400-feet level would not be permanent. The total quantity of ore taken from this mine from January 1 till July 15, 1867, was 8,382,855 pounds; total quantity since it was opened in 1861, 108,731,678 pounds; all of which has been exported to the Atlantic States and Europe,

except about 2,376,000 pounds, or 1,000 tons, portions of which remain at the mine, at Stockton, and San Francisco, ready for shipment.

THE KEYSTONE MINE.-Explorations in this mine have been extensive and costly during the past year. The cross-cut toward the south line, in the sixth level, at a depth of 350 feet, running from the south or Houghton shaft, struck the main lode where it was 10 feet wide, of 15 per cent. ore. It was deemed best to sink the main shaft 200 feet, to avoid the necessity of working by a winze at so great a distance from the shaft, as it was calculated the shaft would strike the ode at that depth. At the depth of 552 feet a cross-cut was made 43 feet in length before the lode was reached. Its width at that depth could not be ascertained, owing to the great increase of water, which prevented the men drifting till a sufficiently large sump-hole could be made.

The company have taken out but little ore during the past year, having ceased operations, except for exploration, early in April. At present they only employ a few men to attend the machinery and pumps, to keep the mine from filling with water. The total receipts from the sale of ores taken from this mine amount to $375,000. The amount of assessments collected exceed $100,000, the whole of which has been expended in developing the mine and purchasing machinery. The company has never declared a dividend.

THE OTHER COPPEROPOLIS MINES.-The Empire, Consolidated, and Inimitable were worked to some extent in the spring; but have been idle for several months. The owners of the latter mine (which is parallel and immediately adjoining the Union) had sued that company for taking out ore from their ground. The case attracted considerable attention from its novelty and the value of the interests involved. It was decided in favor of the Union Company. THE NAPOLEON MINE.The new shaft on this mine was sunk to the depth of 195 feet, when work was suspended. No ore has been taken from it during 1867. THE CAMPO SECO MINE.-This mine has been partially worked for a few months during the present year. Smelting works were erected by the company as early as November, 1865, and arrangements made for working economically. A railroad a mile in length was constructed for the purpose of conveying the ores from the mine to the furnace. By a judicious arrangement in the location of the works, the ore, after reaching the surface through the shaft, is carried down to the furnaces by its own weight, and these being located on the banks of the Mokelumne river, the slag and other waste is dumped into that river at trifling cost for labor.

The smelting works consist of two cupola furnaces and a McKenzie blast, moved by a water wheel, and a roasting kiln. The furnaces are built of sandstone and lined with steatite, both of which materials are abundant in the neighborhood of the works, and appear to be tolerably well adapted for the purpose. The object of the company in erecting these works was not to make copper or matte of a high standard, but to concentrate the ores obtained below 10 per cent. into about 35 per cent. regulus. The experience of the persons in charge confirms the remarks heretofore made in relation to the impolicy of each mine smelting its own ores. The ores here, like the bulk of all obtained from the mines on the cupriferous belt which traverses the State from north to south, are nearly pure sulphides of iron and copper, rarely containing more than five per cent of silica, and consequently difficult to reduce alone. The average assay 20 samples shows 45 per cent. sulphur, 40 per cent. iron, 6 to 10 per cent. copper, the remainder being silica, water, &c. To reduce such an ore to regulus it was found necessary to add 20 per cent. of quartz, in order to supply sufficient silica to combine with the iron after the liberation of that metal from the sulphur. Had silicates of copper or ores containing a considerable percentage of quartzose gangue rock been available, a much larger product of copper would have been obtained at the same cost of fuel, flux, and labor.

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Even in the processes for roasting the ores in kilns the absence of silica is

a great disadvantage and source of loss. The sulphur, when in such excess, as in this class of ores, when heated, coats the ores, forming a refractory material for future operations.

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The two furnaces on this mine, when in full operation, smelted about eight tons of ore and 20 per cent. of quartz in 24 hours. To do this it required 250 bushels of charcoal daily, which cost about 20 cents per bushel; two men to attend the furnace as smelters, two to supply materials, two to carry off the slag, which, owing to the large proportion of iron and the nature of the flux, was large, and two others to prepare the materials for the furnace feeders. Most of the work was performed by Chinese labor.

THE LANCHA PLANA MINES.-These mines being under the control of the proprietors of the Union, have not been worked during the year.

THE MINES IN AMADOR COUNTY.-The Newton, Cosumnes, and Pioneer mines, in this county, ceased operations in April, 1867.

THE MINES IN MARIPOSA COUNTY.-The principal mine in this county, La Victorie, owing as much to disagreements among its stockholders as to the depreciation in the value of ores, has been idle nearly the whole of the present year. Having given a description of this mine in previous report, the following particulars relating to its working will be interesting for reference: After an examination made by order of the company, the engineer in his report states that the mine from the tunnel has been well opened. The foot-wall, where the tunnel enters the vein, is well defined; but, as yet, the hanging wall had not been found, although the vein had been pierced about 70 feet. Two thousand tons of ore had been taken out of the mine, chiefly from pockets or smaller veins, mixed with the materials which had been thrown into the larger vein. A series of deposits of ore exists above the foot-wall, more or less connected, containing quantities of black oxide, and until the works are carried below the surface disturbances the size, value, or permanency of the lode cannot be determined. From the indications in the present workings there is reason to believe the mine will prove permanent and valuable. The company not having the means to obtain proper machinery, had done the best they could under the circumstances. The mine is well timbered, and is in good condition for future operations.

A shaft had been sunk about 90 feet, on an incline which it was supposed would intersect the lode. But by a cross-cut run from the bottom it was found that the lode had changed in dip. The shaft was therefore sunk nearly vertical, so as to strike it about 80 feet below, or on a level with the tunnel. While running this cross-cut, seams and deposits of black oxide were met with.

ore.

The extraction of ores while the mine was worked was slow and costly, owing to the broken nature of the country rock. The difficulties that beset the coinpany are in part due to the isolated locality of the mine. It is too far from any travelled road to obtain the advantage of cheap transportation by teams returning empty from the mountains. The nearest point of shipment is 84 miles, over a rough country. The cost of transportation swallowed up the value of the In addition to this, the company conducted its business on the same extravagant scale as the richest of the Washoe companies. Its officers, salaries, office rent in San Francisco, and incidental expenses outside the mine amounted to $16,000 per annum. There are few undeveloped mines that could stand such a drain. Under more economical management, and with cheaper transportation, this mine might add something to the wealth of the State, even at the present low price of copper. Its ores are abundant, and of a higher grade than the average.

THE BUCHANAN MINE is located in Hunter's valley, Mariposa county, and has been worked at intervals during the past year. The shaft, in June, had reached 150 feet in depth, where the lode was found to be seven feet wide, of tolerably compact sulphurets. Having oxides, silicates, and carbonates convenient to the smelting works, this company, during the year, has made 100 tons of

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