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doubtful whether any permanent mine will be discovered in the southern district of this county. Some activity has been imparted to this district during the past year by the erection of several smelting furnaces on a small scale, which, operating on the silicates, oxides, and carbonates of the metal, which are found in great abundance for miles around, make large quantities of regulus and black copper from 60 per cent. to 96 per cent. of fineness. The owners of these furnaces pay a fair price of all the ores of a suitable character the miners can bring. This will account for the activity in the district and for the shallowness of the explorations, as the ores cease to be of the class required at a few feet below the surface.

One of these furnaces has been erected on James's ranch, and another, about six miles distant, on the border of Fresno county, at Buchanan Hollow. From this latter place about one hundred and fifty tons of copper, in bars ranging from 80 per cent. to 96 per cent. of metal, have been exported from San Francisco to New York by Coffee & Risdon, the proprietors of the works.

The furnaces at James's ranch are constructed on the French plan, introduced on this coast, on the Queen of Bronze mine, in Oregon, by M. De Hierry, a French metallurgist of considerable ability. They are capable of operating on about eight tons of ore in twenty-four hours. The class of ores operated on have averaged about 12 per cent., the greater portion of which has been obtained from the Green Mountain and Lone Tree mines, near the works.

The company obtain plenty of pine wood charcoal at $70 to $80 per ton. All the smelting is done with this description of fuel. About a ton of this charcoal is required to produce a ton of marketable regulus. There are about a dozen men employed at each of these works.

The furnaces used at Buchanan Hollow are what are known as Haskell's water-lined, a brief description of which will be found under the head of "Processes," &c. They are of about the same capacity as those mentioned above, and consume about the same quantity of the same description of fuel. There are several of this latter description of furnaces in use in this State; one on the Cosumnes mine, in Amador county; another on the La Victoire mine, in Mariposa county, and several others are in an advanced state of construction in various localities.

About six miles south of these smelting works at Buchanan Hollow there are several of the best mines in this county; among them is the Bachman. In the shaft on this mine, at a depth of sixty feet, the lode is ten feet wide, composed of yellow sulphurets, identical in appearance and composition with those found at Copperopolis and Campo Seco, and accompanied with all the characteristics of the lodes in those districts, and affording many facts to prove a connection in the origin of all of them.

Near the smelting works on James's ranch there is a series of lodes, traceable for about ten miles, and ranging N. 24° W., corresponding very closely with those already noticed in Salt Spring valley. In a shaft sunk on the Dozer lode, one of this series, at a depth of eighty feet it was found to be six feet wide, composed of nearly solid yellow sulphuret. But, as was explained above, the disturbance of the containing rock does not hold out a reasonable hope of the permanence of any body of ore in the district.

Mr. Haskell, the proprietor of the Buchanan lode, has recently sold it and the smelting works above described to a firm at Stockton for $22,000. This will afford a basis on which to estimate the value of the best mines in the district.

The "La Victoire" mine, in Hunter's valley, is a most valuable property, being second in importance to scarcely any copper mine in the State. It is located in a section of this county which has not been affected by those disturbing causes which have broken up the lodes in all the other sections. It also possesses the very great advantage of having an immense body of very

good ore above the level of the surrounding country, which enables the company to extract it without the use of expensive hoisting and pumping machinery. The lode runs through a hill several hundred feet in length and nearly three hundred feet high, cropping out on the very summit of it, and traceable, unbroken, through its entire length, at an average width of nearly five feet. The proprietors, who are mostly Frenchmen, have sunk shafts on the lode at both ends of the base of this hill to the depth of nearly two hundred feet, without discovering any material difference in its appearance, the only important change being that, while the lode dips to the east at an angle of 450 at twenty-five feet below the surface, at the base of the hill, at one hundred feet lower, it dips at an angle of 68°; but, as it increases nearly a foot in thickness at the point where the dip changes, it is evident that the change has not been the effect of dislocation. A great deal of very rich ore has been taken out of this mine, much of it containing sufficient gold to pay for working it for that metal only.

It may be proper in this connection to state that the copper bars made in this county by the furnaces described above contain a very large per cent. of gold. Some of it, assayed by Kellogg & Hueston, of San Francisco, was found to contain as high as $450 to the ton. Much of this copper contains $50 in gold to the ton; none of it less than $20.

There is a small smelting furnace on this mine, but it is not in use. For the past year but little work of any kind has been done on the mine in consequence of disagreements among the owners, one portion of whom are playing the game of "freeze out" upon the others.

There are several other good copper mines in this district, but those who own them do not appear to have either the means or disposition to develop them, and capitalists from abroad are afraid to invest very extensively in such mines in this county till they have been better examined.

San Luis Obispo county mines.-The Osos mines in San Luis Obispo county were discovered in the spring of 1864. They are situate about eight miles west of the Old Mission of San Luis Obispo, on the Osos ranch, near the south end of a wide belt of cupriferous ores that is traceable for more than twenty miles to the north, among the range of mountains which lay between the town of San Luis Obispo and the Old Mission of Santa Marguerita. This belt of ore, on which there are a great number of mines, presents very much the same peculiarities as are mentioned in the description of the Hamilton district, in Mariposa county. The disturbance of the lode by subterranean causes has broken it up to such an extent as to render it unprofitable to mine. The Osos district, as is the case with Hunter's valley, in Mariposa, appears to have been less affected by these disturbing causes. A shaft one hundred and ten feet deep has been sunk on the Osos lode, which was from four feet to twelve feet wide. One hundred tons of ore, averaging eighteen per cent., have been shipped from this mine direct to Boston and Swansea, and there are several hundred tons more ready for shipment. Ex-congressman Phelps is extensively interested in these


Los Angeles county mines.-The Solidad district, in Los Angeles county, is located about thirty miles due north from Los Angeles. The knowledge of the existence of copper in this locality was published by M. Duflot de Mofras nearly twenty years ago, as it was somewhere in the neighborhood that placer mining for gold was carried on as far back as 1840. Mr. Bidwell, member of Congress for California, saw these early gold miners at work, and probably saw the croppings of the copper lode, which are quite extensive and conspicuous for a long distance. In 1854 a Frenchman named Maris discovered the mines in what is now known as the Solidad district, but the discovery attracted no attention till the excitement about copper, which followed the discovery of the mines at Salt Springs valley, in 1861 and 1862, when great activity in prospecting raged in this locality, and a great amount of work was

done during the following two years. At present, and for more than a year past, none of the claims have been worked. Among the few important mines in this district are the La Solidad, Copper Hill, and Occidental. On the first named, at the depth of one hundred feet, the lode was found to be about seven feet wide. This is the deepest shaft in the district.

The geological formations and ores in this district are precisely the same as those already described in San Luis Obispo and Mariposa counties, and the same disturbing causes have broken up the lodes, which range in the same direction within a few degrees.

Plumas county mines.-The copper mines in Genessee valley, Plumas county, are the highest on this coast, the valley in which they are located being a small basin of a few miles in circumference, embosomed high up among some of the loftiest peaks of the Sierra Nevadas, which are clustered together in the northeast of this county. This portion of Upper Plumas contains some of the most magnificent scenery to be found on the coast. Immense granite ridges are seen rising bare and bleak two and sometimes three thousand feet above the densely wooded ridges at their base, while below, cañons thousands of feet deep form courses for the waters, which look like silver threads as they go meandering through the black gorges that lead them to unite with the waters of the Feather river, thousands of feet still further below. Nature appears to have performed some of her mightiest labors in this locality. Subterranean fires have piled up the molten rocks thousands of feet high, for the highest peaks are composed of lava, while the floods of water have worn the frightful cañons which furnish the bed for the present insignificant streams. Amid the very centre of so much ruggedness, caused by nature's greatest forces, Genessee valley forms a beautiful contrast, with its grassy fields and the curling smoke of its smelting furnaces and other evidences of the power of man. The belt of copper ores already referred to passes through this valley in a course ranging north twentyfive degrees west. As may well be imagined, in such a country, the lode has been extensively dislocated; but by examining the unshifted bodies of the containing slates, which may be traced for many miles, as well as the form and composition of the lodes, it is proved that this is part of that great belt. The chief copper mines, the Cosmopolitan, are located about five miles from the village of Taylorville, and three-fourths of a mile from a ranch which was originally located in the valley by a Mr. Gifford. They were discovered in the beginning of 1862. The inaccessibility of the place and the broken character of the country preclude the possibility of this ever becoming a very important copper mining locality. Nevertheless, parties interested in these mines have erected smelting works which have cost upwards of $30,000, and made several tons of good regulus by a process invented by a farmer named J. C. Chapman, who never had any knowledge or experience in copper smelting till the discovery of these mines. As long as the parties interested in this enterprise could obtain plenty of oxides, carbonates, and silicates of the metal, which were quite abundant and very rich at the commencement of their operations, they obtained regulus sufficient to pay expenses; but as soon as they reached the sulphurets in the lode the works had to stop, as they were not adapted to operate on this class of ores. At the present time they are not in operation. These works were put up by

Bolinger, Blood & Co.

At a depth of sixty feet the lode on the Cosmopolitan mine was found to be about fourteen feet wide, containing about ten per cent. of metal. It lies between the granite and limestone on this claim. The metamorphic slates and serpentine, which accompany the copper all through this State, are here a few hundred feet to the south.

Del Norte county mines.-The Alta district, in Del Norte county, is situated on what is known as the "low divide," an extensive plateau on the summit of a lofty range of mountains which divide the valley of the Illinois river from the

Pacific ocean. These mountains run through the northern portion of California and the south of Oregon, for more than one hundred miles, and cross the western branch of the Sierra Nevadas at nearly right angles.

Altaville, the centre of this district, is about fifteen miles northeast from Crescent City, Del Norte county. There are a great number of mines in the district; many of them have been extensively worked, and probably one thousand tons of good ore has been shipped from them since their discovery, in 1860. Among those which have shipped ore are the Alta, Union, Pacific, Lady Belle, Chrysopolis, Comstock, Diamond, Express, Pearl, Copper Hill, Excelsior, and a number of others. The Alta was the first mine worked in the district, and is the only one worked at present.

The mines in this district are not connected with the great copper belt so frequently alluded to in this report. This runs several miles to the east, where the Siskiyou mountains connect the counties of Yreka, in California, with Josephine, in Oregon. The ores in the Alta district are quite distinct in deposition, appearance, and character from those found in the mines on the great belt. The deposits are separate and distinct; of probably the same age and origin, as they are similar in other respects to those found around the base of Mount Diablo, and in the coast range further south. The first forty-two tons of ore shipped by the Alta company averaged forty-five per cent., and sold in San Francisco for $7,000 cash, the cost of their extraction and delivery not exceeding $2,000. They were red oxides, chiefly, of which there was a large body nearly three feet wide and fifty feet long, near the surface, but this was soon exhausted, as there is no well defined lode on the ground. In fact it is doubtful whether there is a consecutive body of ore of fifty feet in length in the whole district. The croppings of what are supposed to be lodes-nearly a dozen of them—are seen ranging nearly north and south for many miles, but the body of ore beneath these croppings is so irregular in position, owing to the distortion of the serpentine in which they are contained, that it is almost impossible to tell in what direction the average of them do lie.

The Alta Company have sunk a shaft on their mine to the depth of nearly four hundred feet without finding a regularly defined lode. They meet with bunches of ore, chiefly yellow sulphurets of a very low grade, varying in size from a mere film to ten feet thick, but not sufficiently connected to make the mine profitable to work under the existing state of the copper market. This mine is exceedingly well situated for obtaining its ore cheap, if a large body of it should be found, as drifts could be run into the hill at a great depth at comparatively little cost.

The Rockland district is located about fifteen miles east of the Alta district, above described, and about thirty miles from Crescent City, Del Norte county, California. The mines in this district are located on the great copper belt, which may easily be traced in the vicinity for nearly twenty miles, in the direction of N. 28° W., the general trend of this belt, by which it may be followed from where first noticed, north of Los Angeles, to about twenty-five miles west of this district, which is a few miles within the limits of the State of Oregon. There are several other districts within this State in which important copper mines have been located on this belt; but time will not admit of any reference being made to them. The Queen of Bronze, near Waldo, Josephine county, the most valuable copper mine in Oregon, is located on this belt, about sixteen miles west from this point. Extensive smelting works have been erected on this latter mine, and thousands of tons of ore have been exported from these mines, which, as has been already stated, have been discovered since 1860.

There are some peculiarly interesting features connected with the copper mines of this district, which have a tendency to throw considerable light upon the subject of the action of volcanic forces on metallic ores, because in this vicinity an enormous volcanic dyke, nearly one hundred feet wide, approaches

the copper belt at an obtuse angle, within a hundred feet, and it is within this point of proximity that the large masses of metallic copper mentioned above were discovered. Another point in the same connection may be here mentioned. The age of the rocks containing the copper, throughout the whole extent of the great belt, has been tolerably well ascertained to be between the triassic and tertiary eras, and as this volcanic force, which has caused the conversion of the ores into metals from one end of it to the other, must have been exerted subsequently, the opportunity here afforded to examine the largest and most clearly defined dyke on the coast is very important.

Mount Drablo district.-The principal copper mines in the Mount Diablo district are located about the northern base, and up the side of a spur of Mount Diablo, called Mount Zion, and along the north side of Mitchell's cañon, near the town of Clayton, Contra Costa county. The first discovery of these mines was made in 1860, and considerable work was done on several of them for about two years, in efforts to discover the lode, but without success, as there is no lode in the mountain. The copper found here is not connected with the great cupriferous belt, but exists in detached bunches and masses, as is the case in the Alta district, in Del Norte county, described above. The croppings of the patches of ore here run north and south, as they do at Del Norte. Some metallic copper has been found on the north side of Mitchell's cañon, but in every case, after reaching a few feet below the surface, the ore, when found in bodies sufficiently large to take out, has been found of a very low grade; ten tons of selected ore shipped by the Keokuk company did not yield more than eight per cent. It is doubtful whether the mines in this district will ever pay to work.

Peavine district.-The Peavine district was discovered in 1864. It is located a few miles east of the Henness pass, in Washoe county, Nevada, one portion of it being within three miles of the line of the Central Pacific railroad. The district embraces an era of ten miles square, in which there are a great number of claims of considerable importance. The ores in all these mines are entirely distinct from those found in California, as well as the containing rocks. They are usually much contaminated with quartz, but they contain a large per cent. of gold and silver. The completion of the Central Pacific railroad to within a few miles of the district has given considerable impetus to prospecting, and a great number of companies are preparing to take out ore, the railroad company having informed those interested that it would carry ores to Sacramento, from any point in the Henness pass, for $9 per ton. The ores of most of these mines being silicates, carbonates, and oxides, are very easily concentrated, a fact which the owners of the Bay State mine appear to be aware of, as they are putting up a small furnace, on Haskell's plan, to operate on all the ores they can purchase, as well as what they can obtain from their own mine. No ores of any consequence have been shipped from this district, in consequence of the distance to a market; but in 1864 à Doctor Landszwert made a number of large bars of fine copper from them, which were exhibited at the State fair, at Carson City, in that year. These bars contained $150 per ton in gold, and about $250 per ton in silver, according to the doctor's assay.

Lower California mines-Of the copper mines in Lower California but little of an authentic character is known. The Sancè mine, as described by Mr. W. Thompson, an old Cornish miner, who was superintendent of it for three or four years, is located near Loretto, a place in the province of Comondu, about thirty miles from the coast, where there is a good harbor. The lode is described as being from eight to ten feet wide, enclosed between walls of slate and granite. It has been extensively explored by shafts and levels, and about five hundred tons of ore have been shipped to Europe, where it sold for about five hundred dollars per ton. This ore, specimens of which have been brought to San Francisco, is of a very peculiar character, being a sort of talcose gangue,

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