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bullion contains only silver and gold, and perhaps a little copper. The oxides of arsenic and antimony, when skimmed from the surface of the bullion, get mixed with some metallic lead and oxide of lead. The scum The scum of antimony is of arsenic is returned to the blast furnace. desilverized, and then reduced to a metallic state. The desilverizing furnace is a reverberatory furnace, and in it the scum of antimony from the softening furnace is subjected to a low red heat, and treated with coal slack, sawdust, or any reducing agent, by which a bullion carrying lead, some antimony, and gold and silver is formed; also antimony slag, consisting mainly of the oxides of lead and antimony, and practically no silver. The bullion from the desilverizing The antimony slag is furnace is returned to the softening furnace. reduced to a metallic state in a blast furnace, forming antimonial lead, carrying about 40 per cent antimony. The bullion, which is, of course, the main product of the softening furnace, is treated, as before mentioned, by a modification of the Parkes process. In the zincing pots of this process it is melted and treated with about one pound of zinc for every ounce of gold or silver the bullion may contain. The zinc is added in three separate charges. After being thoroughly mixed the contents of the zincing pots are allowed to stand and cool for half an hour, when a zinc scum, which is an alloy of gold, silver, lead, and zinc, and copper if present, rises to the surface; this scum is removed and the remaining lead contains less than 10 cents in gold and silver to the ton.

The lead bullion, which contains perhaps one half of one per cent of zinc, is drawn off into market lead furnaces. In these furnaces, the lead is subjected to a low red heat, and a zinc dross forms, containing 70 or 80 per cent of lead, which is returned to the blast furnace; the refined lead bullion is then market lead, and is run into pigs for shipment.

The skimmings from the zinc pots may be regarded as a "wet alloy" of lead, with zinc, gold, and silver, and possibly a small amount of copper. This alloy is treated in a "sweat furnace," i. e., a reverberatory furnace, where a low temperature is employed. In this furnace, a bullion containing from 60 to 80 ounces of precious metals to the ton separates from the residue and is returned to the softening furnace. The residue is a dry alloy of lead, zinc, gold, and silver, and any copper that may be present. The dry alloy is then retorted in graphite retorts, where the zinc is driven off; 65 per cent of zinc is recovered and used again in the zincing pots. When the zinc is driven off, the 'dry alloy forms high-grade bullion, which is cupelled. The products of the cupel`lation are litharge, carrying off any copper that may be present (which is returned to the blast furnace), and gold or silver bullion. The gold. and silver bullion is parted by sulphuric acid, and the silver precipitated from the resultant solution by metallic copper. About 50 per cent of the sulphuric acid fumes from the parting process is recovered by condensation, in the condensing chamber previously mentioned.

The copper solution resulting from this process contains a large amount of free acid, which is used for treating the second matte, as previously stated; the sulphate of copper is crystallized and sold as bluestone-more than 1,000 tons of bluestone being manufactured annually in this department. The residue from the second matte, which remains undissolved, and contains gold, silver, and lead, is returned to the blast furnace.

The annual output from the Selby Reduction Works is about as

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Bullion, etc., refined

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The rates for treating gold and silver ores and concentrates at the Selby Works are no higher than those of Eastern reduction works, and the freights from all parts of California to the Selby Works are necessarily lower than to Eastern refineries. Under these conditions, there is no excuse for smelting ores or concentrates leaving this State.

Lime from the Dickie ranch, near Suisun, in Solano County, is now used extensively as a flux at these works. At the time of the writer's visit a new contract for 2,000 tons was being made, several thousand tons having been used since the attention of this firm was drawn to the deposit by the California State Mining Bureau, in 1891.

A large amount of the lead reduced by Selby & Co. is used at their shot tower and lead works, in San Francisco, where they manufacture lead pipe, sheet lead, shot, solder, etc.

An important branch of the business of the Selby Works is the manufacture of the Standard machine-loaded cartridges (Chamberlain patent). At the cartridge factory, located adjacent to the smelting works, eight machines, working automatically, turn out an average of 12,000 cartridges a day to each machine.

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EMPIRE COAL MINE.

The Empire Mine and Railroad, as is well known, is operated by Messrs. Belshaw & Judson. Their coal property embraces about 760 acres. During 1890-91 mining was carried on by them at West Hartley and at Stewartsville, about one hundred men being employed.

The output of coal from the mines operated by this firm, for the two years ending with May, 1892, has averaged about 2,500 tons a month. Most of this was shipped from Antioch, and some carried by the S. P. R. R. The price has averaged $3 50 a ton, f. o. b. at the wharf, or on the cars at Antioch. A portion of this coal came from Stewartsville, and a portion from West Hartley.

At the time of the writer's visit to Contra Costa County, in May, 1892, work was being carried on by Messrs. Belshaw & Judson at Stewartsville, and at Cocoran's Mine.

At the latter mine a slope of 425 feet had been run in a southerly direction at an angle of about 26.5°, the dip of the formation being about 26° to the north. The first "lift" run upon this incline was at a depth of 212 feet, where the vein, which is known as the "Little Vein," was 2 feet 4 inches in thickness. All the coal was worked out of the first lift, and the incline continued to a depth of 425 feet. At this depth a drift was run back to the vein for a distance of about 420 feet, the vein there being about the same thickness as before noted. states that about 15,000 tons of coal have been taken out of this mine Mr. Belshaw since it was reopened by this firm; the output was good, clean coal. The water is controlled by a 300-gallon tank, which is hoisted about seventy times in twenty-four hours.

Mr. Belshaw also states that a new vein was struck while running an

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air shoot in the Central Mine, at Stewartsville. This vein lies between the Black Diamond and the "Little Vein," being about 225 feet horizontally to the south of the "Little Vein." This new vein was 3 feet thick when first struck, and when encountered at a higher level, in the air shoot, about 150 feet above, it was found to be about 24 feet in thickness. When struck at a still higher level, about 500 feet above the point where The it was first observed, it was found to be about 2 feet in thickness; but 80 feet nearer the surface, the quality of the coal had deteriorated. new vein was named the “Belshaw Vein."

THE PITTSBURG COAL MINE.

The shaft, which was commenced in 1889, was finished in 1891, terminating at a depth of about 600 feet. The shaft, penetrated the old workings on the "Clark Vein," at a depth of about 300 feet, and the The "Little "Little Vein," at a depth of about 450 feet. The dip of the formation at this point is to the north at an angle of about 30°.· Vein" at this depth showed a thickness of about 18 inches. From the bottom of the shaft a tunnel was run in a northerly direction, which intersected the "Little Vein" at a distance of about 160 feet from the bottom of the shaft. At this point the "Little Vein" showed a thickness of 2 feet 2 inches of good coal. The water was controlled by a tank holding 380 gallons, which was elevated by the hoist used for raising the coal and rock.

It is the opinion of Mr. Rankin, the Superintendent of the mine, that the coal probably increases in thickness from this point westward along the strike of the vein; for in the old workings of the Eureka Mine, distant about 1,000 feet in a westerly direction, the vein showed a thickness of 2 feet 6 inches of good coal. Mr. Rankin states that a vein of these dimensions could be mined at a profit, calculating the coal at $3 50 per ton, f. o. b. at Pittsburg Landing.

It is the intention of Mr. Rankin to drift farther north to the "Clark Vein," which would be struck at a distance of about 350 feet from the bottom of the shaft. This vein, in other workings of the Pittsburg Mine, showed from 3 to 4 feet of good coal. The largest portion of the vein upon this property remains intact. Prospect work was suspended on these levels in consequence of the low price of coal. The company, at the time of this writing, was working the "Black Diamond Vein,” at a point about 1,000 feet west from the new shaft.

In 1891-92 the main incline on this portion of the property was `extended about 227 feet in a southerly direction, and a drift was run from the end of it in a northerly direction for a distance of 320 feet before the vein was again struck. The formation penetrated was similar to that in the other workings, the pitch being from 26° to 30° to the north. At this point the "Black Diamond Vein" showed a thickness of 34 feet of good coal.

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Mr. Rankin states that the price of coal at the Pittsburg Landing averaged, during 1891-92, from $3 to $3 50 per ton. The company operating these mines was incorporated in Contra Costa County, October 1, 1861, under the name of the Pittsburg Mining Company. This com pany now controls the property of the Eureka and the Independent Mines, comprising about 480 acres of coal land, of which Mr. Rankin states that there are about 200 acres of good coal land yet untouched.

WATER AND WELLS.

The proprietors of Byron Springs, after boring 116 feet through the conglomerate, succeeded in obtaining only brackish water; they therefore abandoned the idea of obtaining a supply of fresh water from the solid formation around the springs, and established a pumping plant to pump water from the San Joaquin River 2 miles distant, and about 90 feet below the hotel grounds. For this purpose, a Dow pump, having a capacity of 55,000 gallons per hour, is used and operated by a forty horsepower engine. The pipe-line is 6-inch pipe, 4,700 feet of it being supported on trestles over the "tule,” and the remainder buried 3 feet beneath the surface of the ground. In driving stakes for trestle, the "tule mud" was found to be, in many places, 30 feet in depth.

On the Quinn ranch, 4 or 5 miles east from Martinez, on the Government tract, a flowing well is said to have been obtained at a depth of 80 feet, which yielded an inch stream of water.

Shallow flowing wells are reported in the Pacheco Valley; also, on the east side of Walnut Creek, near Concord, a flowing well was obtained at a depth of about 160 feet, the water flowing just over the top of the casing. On the west side of the creek borings have been made to the depth of 300 feet without obtaining flowing water.

At Walnut Creek, near Concord, the following formation has been observed:

Sandy loam Yellow clay. Gravel

50 to 60 feet. 3 to 20 feet. 1 to 2 feet.

This last stratum contains a good supply of water, but it does not rise in the casing.

In and around Martinez, dug wells on the bottom lands have shown a clayey soil, passing into bluish clay for a depth of from 30 to 40 feet. Water is found in thin strata of sand and gravel, with which the clay is interstratified.

In 1877-78 several borings were made by the S. P. R. R. Co. in the bed of the Carquinez Straits, between Benicia and the Contra Costa shore, toward Martinez. A bedrock of sandstone, overlaid by a thin stratum of red clay, was struck beneath about 40 feet of river mud, clay, sand, and gravel. One of the borings a short distance from the Martinez shore showed the following formation:

Soft mud and clay

Sand and gravel

Very stiff clay

Beneath the stiff clay sandstone was struck.

36 feet.

14 feet.

18 feet.

3 feet.

3 feet..

When the writer last visited Martinez, several citizens questioned him with regard to the possibility of obtaining water from flowing wells at Martinez in sufficient quantity to supply the town. It is evident from the position of Martinez, that the geological conditions are not present to warrant any one calculating on obtaining a flowing well of great volume in that neighborhood. It is not impossible that small veins of water might be struck by boring, such as give rise to springs, or accidentally to shallow flowing wells, in hilly or mountainous portions of the

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country; but it is unlikely that any flowing well could be obtained by boring that would yield a sufficient volume of water to supply the town. It is certain from the position of Martinez, and this is corroborated by the borings of the S. P. R. R. Co., that the bedrock can be at no great depth. The experimental wells, bored at Benicia and at Byron Springs, attest what has frequently been shown, viz.: that the wells bored in the sedimentary bedrocks are seldom very satisfactory. When the water has to be sought in the solid formation, a tunnel is usually preferable to deep boring. It is more than likely that the best and most reliable subterranean water supply at Martinez is to be found on the face of the bedrock, or in a clayey stratum covering it, probably at a depth of something less than 100 feet. If an experimental boring should show this to be the case, a dug well of great diameter would afford the best supply.

DEL NORTE COUNTY.

By W. L. WATTS, Assistant in the Field.

At the time of the writer's visit to Del Norte, in 1891, the mining interests of the county were practically confined to placer mining on a small scale along the tributaries of Smith River.

As a perusal of the following pages will show, Del Norte is one of the few places in California where the poor man still earns a living with sluice and rocker, and recent prospecting has demonstrated that there are deposits of auriferous gravel in the county which are yet unworked. Although the position of many of these deposits seems to place them above the reach of the streams, it is probable that they could be worked by impounding rain water; more especially as the rainfall in the northwestern corner of California is somewhat excessive during the winter months. It is also more than likely that there are auriferous gravels in places now covered with forests, which will some day be available. In some places near the seashore, unaltered sandstone sometimes affords a good building material. Inland, the principal geological features to the west of the Siskiyou Mountains are the large belts of serpentine, which here and there are interspersed with more or less metamorphosed shales and sandstones, or pass into talcose slates. The latter formation, which is traversed by numerous little quartz veins and veinlets, extends throughout a large area in the southern portion of Del Norte, and into Humboldt County, where it is first encountered on the seashore to the north of the Big Lagoon. The more compact serpentine appears to be the repository of the chrome and the copper, while its few auriferous veins are not sufficient to account for the gold-bearing sands and gravels which have been deposited during recent geological times. It is probable that the numerous quartz veins and veinlets traversing the talcose slate were the original habitat of much of the placer gold in Del Norte County, for not only does the slate in many places form the bedrock of placer workings, but the gold on its surface is frequently found with rough quartz adhering to it, showing that it has not traveled very far. the other hand, it appears from the character of some of the pebbles in the auriferous gravels, that a portion has come from other formations in the Siskiyou Mountains.

On

A large amount of chromic iron still remains in Del Norte County, awaiting the time when the demand for that mineral shall warrant its being mined and placed upon the market.

The copper interests of Del Norte County at present appear to be at a standstill.

PLACER MINING.

Myrtle Creek Placer Mines.-Placer mining is carried on to a limited River about 10 miles above its mouth. The formation is gravel and Myrtle Creek, which empties into the main fork of the Smith

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cement. These placers were first mined by Louis Gallise in 1853. Lack of water has heretofore confined operations to the winter months, but a new ditch is now nearly completed, which will allow work to be continued during the greater portion of the year. The gold at Myrtle Creek is all coarse gold. About three years ago a nugget valued at $800 is said to have been found there.

The Siskiyou Fork of Smith River.-New placers have been discovered on this stream, and locations have been made by Jenkins Bros., who have commenced work thereon. It is said that there is a good water supply at this point, and that work can be prosecuted there nearly all the year round. The field occupied by these gravels is said to be extensive, but they have not been sufficiently prospected to define their actual limit.

Bald Hill.-Gold sluicing is carried on at Bald Hill during the winter months.

Big Flat.-Mining is still suspended at the Big Flat Placer Mines, in consequence of litigation. These mines are situated upon Hurdy Gurdy Creek, a tributary of the South Fork of Smith River. A freshet in 1889 greatly damaged the ditch, which conveyed the water a distance of about 9 miles from the upper portion of Hurdy Gurdy Creek to these mines. The company in possession of these mines holds a claim which extends over about 640 acres, on the east bank of Hurdy Gurdy It is said Creek. For seven or eight years they prosecuted hydraulic mining, and at one time they employed more than three hundred men. the water right controlled by this company was generally sufficient to supply the mines for about eight months of the year. The yield was coarse gold, and in a clean-up of $1,600, pieces of gold worth $20, and sometimes worth $40, were obtained, pieces worth from $3 to $5 being of frequent occurrence. The largest piece ever found at these mines weighed 5 ounces. The gold was worth $15 50 an ounce. Fragments of quartz were frequently found clinging to the gold. The bedrock is a talcose slate, traversed by numerous small veins of quartz.

French Hill.-Hydraulic mining is carried on at French Hill, on the Middle Fork of Smith River, near Gasquet, where a "small giant" is in operation; there is also some washing with sluice and rockers.

Craig's Creek.-At Craig's Creek placer mining and ground sluicing are still kept up, the plan employed being to sluice off the top dirt and It is said that returns from this mine the bottom with pick and shovel. creek have been very satisfactory, and that several parties have earned good wages there during the past few years.

Mill Creek.-Drift mining and sluicing are carried on by H. Rice, who owns the mining right of about 20 acres on Mill Creek. His claim is about 6 miles east from Crescent City. He states that for the last twentythree years he has made a comfortable living by these means. The gravel at this point is from 10 to 20 feet in thickness, and the owner says that on the western end of his claim the gravel on the bedrock shows from 3 to 25 cents to the pan. Mr. Rice has prospected this gravel in an easterly direction to a point about half a mile from his house

channel. Upon the bedrock he discovered the trunks of several redwood trees, some of which appeared to have grown upon the spot. The gravel taken from the tunnels, however, paid him only 50 cents a day. Mr. Rice also prospected the gravel in a westerly direction from his house and found pay dirt as far as the eastern bank of Mill Creek, which is distant about a quarter of a mile. Crossing to the western bank of this stream he found a similar gravel, which paid as high as $4 to the wheelbarrow load. The bedrock at this point is somewhat metamorphosed shale, with veinlets of lime and a little quartz. A few yards westward from Mr. Rice's workings, on the western bank of Mill Creek, the writer observed a somewhat altered sandstone, standing at a great angle, the strike being east of north by south of west magnetic, and the dip probably east of south.

Goose Creek.-Prospecting on Goose Creek is said to have shown that small wages could be earned there with sluice and rocker, probably $1 50 a day.

Jones Creek and Vicinity.-Parties who had prospected Jones Creek and the headwaters of the South Fork of Smith River informed the writer that small wages could be made by washing upon these streams. Coon Creek.-A few years ago some washing was done on Coon Creek and its tributaries, and it is said that there are extensive deposits of gravel there, which would pay by hydraulic washing.

Clark Creek.-Drift mining is still prosecuted on Clark Creek near Peacock's, and those engaged in the work are said to earn fair wages.

BEACH MINING.

At Pebble Beach, about 2 miles north from Crescent City, H. Raymond and others operated with a Wood & Garcelon machine in the spring of 1891. A run of about thirty days was made, and seven men were employed. It was a four-pan machine, and was run by a six horsepower engine. The sand, however, is said to have yielded only 10 cents a ton, which was not sufficiently high grade to pay for handling. In 1890 L'Hote, of Napa, experimented with a gold-saving machine on the seashore at Crescent City, but, according to all accounts, it was not a

success.

QUARTZ MINES.

Oranna Mine.-The Crescent City Mine was relocated in 1889 under the name of the Oranna Mine. The average of the ledge is said to assay $26 90 in gold and $1 10 in silver. The mine is owned by J. E. Murphy and parties in Crescent City, who intend to erect a small mill to work

the ore.

Myrtle Creek Quartz Mine.-At Myrtle Creek, a quartz mine and a small mill were operated for about three years up to the time when the mill was destroyed by fire.

Last Chance Mine.-Two years ago, J. Byron located a quartz ledge under the name of Last Chance Mine, about 1 mile south from Gasquet. Preston Peak.-Some valuable discoveries of gold-bearing rock are

where the gravel forms a spur, which runs down from Bald Hill, and 1 The ore is said to have shown $7 per ton in free gold.

crossed by the Old Kelsey trail. Up to this spur he found that the

gravel paid for ground sluicing. The gold he obtained was all coaraid to have been made on the Del Norte side of Preston Peak, but the gold, some pieces being worth $20 each. Mr. Rice ran several tunne iter failed to meet any of the prospecting party.

into the gravel on the above mentioned spur, in order to find the

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COPPER.

BUILDING STONE.

Nothing was being done at the various copper properties in Del Norte County, at the time of the writer's visit.

At the Condon Mine, which is about 38 miles east of Crescent City, the formation is serpentine. The workings at this mine consist of upper and lower tunnels, which for the most part are now caved in. In this mine there is said to be a vein of copper ore 8 or 10 feet thick. The only copper ore which the writer saw at the Condon Mine, besides what was on the dump, was at the mouth of one of the tunnels, where a vein of ferruginous rock showing some copper has been cut through. On the dump are a good many tons of magnetic iron and some copper ore.

There is no road to the Condon Mine, and beyond Big Flat the trail is obliterated.

At the Low Divide the formation is serpentine. At the time of the writer's visit, there were several tons of copper and iron pyrites on the dump, some of which was high-grade ore.

On the eastern side of the divide, between the North Fork of Smith River and Diamond Creek, cuts and tunnels have been made in the serpentine. Around some of the cuts, at the time of the writer's visit, copper ore, principally sulphide, was scattered; some of the ore was highgrade. The writer collected an average sample of this ore; it showed 9 per cent of copper, and had no value in gold or silver.

The now abandoned Oregon stage road runs from Smith River past the Low Divide and Diamond Creek. In 1891 the old road was still passable for light vehicles with good teams, but the bridge over the North Fork of Smith River at Rocklin has been carried away. The river at Rocklin is fordable, except after heavy rains. The restricted dimensions of this report necessitate the omission of the writer's observations on the copper mines of Del Norte County.

QUICKSILVER.

Several years ago some quicksilver claims were located on Diamond Creek. A vein showing cinnabar and native quicksilver was also dis covered in T. 18 N., R. 2 E., H. M., and a shaft about 18 feet in depth was sunk. The formation is serpentine. The property is now owned by F. L. Cooper and H. A. Henry, of Crescent City.

COAL.

At Point St. George, about 2 miles north of Crescent City, coal meas ures crop out on the beach below high-tide mark, and at low water quite a body of coal is said to be exposed.

About six years ago, W. H. Hodgkins, of Crescent City, made two borings, each 160 feet in depth, about 400 yards inland from the coal crop pings, and fully three quarters of a mile apart. A vein of coal about 4 feet in thickness was struck in each instance. It is said that this coal exhibited a wood-like texture. Mr. Hodgkins then bored two other holes, each to a depth of 506 feet; one of these was a mile, and the other a mile and a quarter inland from the coal croppings on the beach Although several pieces of coal were found, no vein was struck. In

none of these holes did the water rise to the surface.

On the Edwards ranch, about 2 miles east from Crescent City, there is a sandstone suitable for building purposes. It is said that this stone was examined and approved by the Lighthouse Board and would have been used by them, but a dispute arose as to the price. The rock is a compact, micaceous sandstone, and crops out near the roadway, where a small amount of stone has been quarried, and where a breast of about 10 feet is exposed. The strata dip in an easterly direction, at an angle of about 15°. The stone is bluish when freshly quarried; some of the strata are of brown sandstone. From the quarry a bench of sandstone extends a distance of about 100 yards to a mound of similar rock, the greater portion of which stands on the land of J. E. Murphy. This mound is probably 2,000 feet in circumference and the top of it is about 50 feet above the roadway. No doubt similar rock could be found in the range of hills which rise still farther to the eastward of Crescent City.

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