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60 per cent, matte, most of which has been forwarded to San Francisco, where it remains at present for want of a market. There can be no better illustration of the reduction in the value of copper than is afforded by the working of this mine. The matte made from its ores in 1865, averaging 60 per cent, of copper, sold at San Francisco for 16 cents per pound. The same grade of matte cannot be sold at present at nine cents per pound.
At JamesV ranch the Green Mountain Company have erected smelting works and made a few tons of matte.
None of the other copper mines in this county have* been worked during the present year.
The Mixes In San Luis Obispo County.—But little having been done towards developing the mines in this county during the present year, there are no new facts to report concerning them.
The Mines In Los Angeles County.—With the exception of prospecting among the claims near the Solidad pass, nothing has been done in this county during the past year.
The Mines In Plumas County.—The Genesee Valley smelting works had to cease operations during the winter owing to the weather, and work has not been resumed since, the price of copper offering no inducements to the proprietors to incur the expense of refitting furnaces and mine.
The Mines In Del Norte County.—With the exception of the Alta none of the copper mines in this county have been worked this year. The Alta company have been engaged in developing their mine. They have sunk their main shaft to the depth of 500 feet, run their tunnel 200 feet, and drifted at several levels, finding bodies of ore which appear to improve in quality as the workings progress. The disturbed and broken character of the formation ceases at 200 feet from the surface. The company has sent 400 tons of ore to San Francisco since January, 1867, which has been reshipped to New York. The average of ore has been about 16 per cent, j but the costs attending its transportation to San Francisco, and reshipment thence to New York, absorbs the value in expenses.
The Mines In Contra Costa County.—None of the copper mines in this county have been worked this year.
The Mines In Nevada County.—Capital and labor have been expended in prospecting the copper mines in the western part of this county, where there is a copper-bearing formation extending across it from north to south, on which many claims have been located and to some extent explored. The lodes are generally large, but the ores are of too low a grade to cover the costs of transportation. Of several hundred tons sent to New York and Swansea the average returns did not exceed nine per cent, of metal. Under more favorable conditions, with cheap labor and transportation, these mines might be made to pay. At present they can only be worked at a loss.
The first shaft in the district, called the Well, because sunk for the purpose of obtaining a supply of water, is near Spenceville, in Rough and Heady township. It was used as a well for five years, till the excitement about copper in 1862, when, on cleaning it out, a deposit of sulphurets was exposed 70 feet wide, and extending to an indefinite length in the direction of the stratification of the enclosing metamorphosed clay slate, with a foot-wall and fluccan. But the ore, only ranging from eight to nine per cent., did not pay for extraction and transport.
The Last Chance, the only mine worked for copper in this county, is located on this belt, near the Empire ranch. It was discovered in 1863, and has since been explored with such satisfactory results as to warrant its owners, who are among the most enterprising citizens in the State, (D. O. Mills, of San Francisco, A. Delano, S. I). Bosworth, and E. W. Roberts, of Grass Valley,) to make application to procure title from the federal government to the land on which the mine is located, the first application of the kind made. A shaft has been sunk to the depth of 200 feet^where the lode is found 12 feet wide, of sulphurets, averaging from 12 to 20 per cent, of metal. Before the rise in price of freight a shipment of this ore to Swansea'returned a profit of $35 per ton. The company own 2,400 feet on this lode.
Considerable excitement was created in this county towards the close of 1866 by the discovery of ores in the Pox mine, from which about 40 tons of oxides and carbonates were shipped to Swansea in October of that year. But the excitement ceased as the price of copper declined, though nearly 100 claims were recorded during the last quarter of 1866.
Several small parcels of ores have been received at San Francisco during the present year from the Western Star and Green mines, located near the Last Chance and on the same lode; but at present and for several months past none of the mines have* been worked.
Other California Copper Mixes.—With the exception of the Union Company, who own a mine in Marin county which they prospected lor a few months in the spring, the above is a full statement of tiie progress made in copper mining in California during the year 1S67.
The Oregon Copper Mines.—The Queen of Bronze and other mines in this State have been idle during 'the past year. New discoveries have been made, but none of them have been developed sufficiently to prove their value. They are referred to merely to show the extent of country on this coast in which copper has been discovered.
The most important of th§ discoveries have been made in the southern part of Douglas county, where croppings of ore exist, not in the form of gossan, as in California, but as masses of oxides and carbonates, which will be of importance if extensive smelting works should be erected.
The' mines on Eagle creek, Baker county, have been explored with such results as to have induced the owners to enter into a contract with the Oregon Steam Navigation Company to carry their ores to San Francisco, at a stipulated price, for a year.
The Lower California Copper Mines.—The Sance mine, at Loretto, has not been worked during the past year. The shaft on this mine has reached the depth of 114 feet, where the lode is seven feet wide, the ore said to average 12 per cent.
A few tons of ore w^ere received occasionally at San Francisco from mines along the lower coast, during the past spring, but such shipments have entirely ceased for several months.
The Copper Mines Of Nevada*—Most of the ores found in the district of Pahranagat, though generally famous for the silver they contain, are more properly described as copper ores. They consist chiefly of gray copper, copper pyrites, erubescite, and other familiar ores of copper, combined with sulphites of silver, lead, iron, zinc, &c. No gold has yet been found in the district. These ores are contained in a quartzose veinstone in some ledges; in others the gangue rock is calcspar, (a carbonate of lime.) Some of the ores contain as high as 50 per cent, of copper. This district lies in the extreme southeast corner of Nevada, where it joins Utah and Arizona, in 37° 37' north latitude and 112° longitude west from Greenwich. The mineral wealth of the district is contained in a range of mountains about six miles long and four miles wide, running nearly north and south, the general name for which is Mount Irish, though each peak has a separate name. Some of the crests of the range tower to the height of UjOOO feet,' and are covered with perpetual snow. The lodes present the characteristics of true fissure veins, and appear to consist of several series, crossing each other in some places at right angles, the whole being contained in a metamorphosed limestone formation. In any other locality they would be valuable for copper mining.
* Described more fully in the section on Nevada.
Similar ores are obtained in the ■mines of Inyo and Mono counties, California. These, however, contain a per cent, of gold. These ores are refractory when worked by the ordinary mill processes. Some of this class of ore taken from the Oamanche mine, in Mono county, and sent to Swansea for reduction, returned $1,000 per ton in gold, silver, and copper. The mines in Kearsarge, Fish Springs, Aurora, and other districts among the higher divisions of the Sierra Nevada produce similar ores. The completion of the Central Pacific railroad will be of great benefit to the miners of this extensive mineral region, particularly if a process shall be discovered by which the gold and silver can be extracted without wasting the copper they contain^—a contingency quite possible1. If such an establishment for smelting as the interests of the coast demand were erected at some point convenient to water and railroad carnage, the refractory ores of the Sierras would become valuable.
The Peavine Mines.—In November, 1866, several tons of ores from this district were brought to Sacramento by the Central Pacific railroad, which passes within three miles of it, being the first shipment from the Sierras by railroad. The total cost for freight by railroad and steamboat was $12 per ton.
Two of'Haskell's water-lined furnaces have since been erected in the district, one to operate for silver, the other for copper, but neither has yet been completed. The ores are chiefly carbonates and silicates, and the furnaces will probably be able to reduce them to a portable form for transportation. As they contain a per centum of gold and silver it may be found profitable to ship them to Europe for separation, till suitable works shall be erected here.
An excellent map of this district has been published by A. J. Hatch, deputy United States surveyor, which will be found useful for reference.
The Mines In Arizona.—The copper mines on Williams fork of the Colorado have been partially worked this year. The developments have been satisfactory so far as, the extent of the lodes and the grade of the ores are concerned, but the difficulties attending smelting operations for want of furnace materials and fuel, the scarcity of means for transport, the high cost of freights from the mines to market, and the low prices paid for ores have caused a cessation of work or confined operations to a limited scale. In March there were 100 men employed at the Central and Planet mines, and about 150 about the works at Aubrey City, nearly all of whom have since been discharged.
The receipts of ores from these mines since January 1, 1867, have amounted to 1,15.6 tons, 600 of which were from the Planet mine. The whole quantity ranged between 20 and 60 per cent, of metal.
The ores in this district would be valuable if suitable smelting works were erected anywhere on this coast, as they are chiefly carbonates, silicates, and oxides.
The Great Central Mine contains 3,600 feet on two parallel lodes, and several hundred feet on other lodes adjacent. The ore is abundant and of good grade, and contains some gold and silver. In May last, the company had about 200 tons, averaging 25 per cent., and 50 tons of selected, averaging 60 per cent., lying on the river bank awaiting transportation. One of the smaller lodes, the "Marion/7 at the depth of 75 feet from the surface, is five feet wide, composed of oxides of iron and copper. At the depth of 125 feet from the surface the main lode exhibits symptoms of sulphur. This, while affording evidence of the "permanence of the lode, is not favorable to smelting operations. For 200 feet on each side of the shaft on the main lode (which is tlie extent of its exploration) it is found to be from five to seven feet wide.
In April last the company completed a furnace capable of reducing 16 tons of ore in 24 hours, and made about 50 tons of coarse copper, ranging from 60 to 70 per cent., which has been sent to New York. But operations ceased in June.
The Planet Mine; though located near the Great Central, contains several
lodes and deposits of ore separate from those worked by that company, and yields ores of a different character. In one of the drifts a body of red, ferruginous, calcareous cement was found, about 18 inches thick, but otherwise of unknown extent, which contains a per cent, of metallic copper in the form of fine spangles and flakes, beautifully crystallized, imparting a peculiar brilliancy to each fracture as the lights of the miners are reflected upon the grains. It differs entirely from other copper ores found on the coast. There are no traces of sulphur.
At the depth of 80 feet, in the main shaft, the lode is composed of a coarse Malachite, or carbonate of copper, nearly eight feet wide, quite compact, and pencilled with dark shadings like green marble. Along the foot wall there are masses of chrysocolla, or silicate of copper—-much of it possessing great beautyappearing like bright green jasper, elegantly marbled with darker green and blue pencillings. Some of these masses, which are susceptible of a high and permanent polish, would be valuable for ornamental purposes.
It is estimated that $100,000 worth of ores have been sold from this mine since 1862.
Mineral Hill Mine.—This and the Empire Flat mine are owned by Greenman & Martin, of San Francisco, a firm long engaged in the purchase of copper ores on this coast. They have erected two furnaces and other works, with a 3,0 horse-power steam engine to run the necessary machinery, at Aubrey City, a town which has sprung up on the banks of the river since the opening of the mines? having expended nearly $100,000 in opening the mines, building a wharf, making roads, &c.
The Springfield Company own the Punta del Cobre mine, and several lodes near the Great Central Company's mine, and there are other mines of probable value in the district.
It is to be regretted that these mines, after having been brought to their present stage of development at so great an expense, have been compelled to cease operations. Only a few hands are now employed to keep the property in order. The furnaces are idle.
The following details of the expenses of transportation from the Aubrey mines may be useful in showing that some of the causes which prevent their development may be removed.
The expenses in bringing ores from the mines to San Francisco sum up about $25 per ton; this, coupled with $i5 per ton freight to Liverpool or New York, makes $40 per ton, without calculating insurance, commission, interest on capital, or costs for mining, which swell the actual cost of the ore to $70 per ton, nearly equal to the present market value of 25 per cent. ore. No further explanation is necessary to show why it is unprofitable to ship even rich ores from this district.
The difficulties in the way of smelting are as discouraging as those attending the exportation of the ores. No suitable materials so far as known can be had in the Territory of which to construct the furnaces. All material has to bo brought from California at a great expense; steatite from El Dorado county and sandstone from Catalina island, &c. Owing to the depredations of the Indians the wood-cutters were unable to go out of sight of the settlement to obtain wood for charcoal, the supply of which was consequently deficient, the quality bad, and the expense enormous; charcoal made of iron wood, musquete, and cottonwood costs $50 per ton. The total product of copper made under these circumstances did not exceed 40 tons.
Under more favorable conditions the mines might be made profitable. There are places along the river banks where 100,000 tons of carbonates and oxides of copper, averaging 18 per cent, of that metal, could be quarried like marble j but such ores are valueless at present.
The following table gives the exports of copper regulus and ores from San Francisco since 1862:
Exports of copper and ores since 1S62.
The above table exhibits the decline in the exports during the present year. A considerable portion of that which has been shipped has not paid expenses, but was sent under contracts previously made.
Copper-smelting Works Erected On'the Pacific Coast.—The following list of copper-smelting works erected on the Pacific coast, though not complete, shows the extent of the business and the amount of capital invested in its development:
List of copper-smelting works erected on the Pacific coast.
* Completed June, 1867.
Several concentrating and roasting works have also been erected near some of the copper mines at considerable expense. The concentrating works on the .Keystone mine? at Copperopolis, cost 850,000. It is quite fair to calculate that $500,000 have been expended in the construction of smelting and concentrating works on this coast during the past four years, nearly all of which has proved a loss for the reasons stated.
Importation Of Metallic Copper.—The increase in ship-building on this coast, and the facilities for repairing large vessels by the construction of docks, &c., at San Francisco, create a demand for sheathing-metal and nails. The general use of copper plates in the quartz mills requires a large supply of this metal, as much of it is destroyed by the chemicals used in the processes for amalgamating the precious metals. The increase in the manufacture of machinery, in the construction of which brass farms a considerable item, and of articles