clay selvage marking the line of the fault plane on either side. In some instances, however, where a brecciated condition of the quartz porphyry is found in contact with the vein, the ore has been deposited to some extent in this broken mass, and in such cases the line of demarkation is not at all plain. These occurrences, together with the branching spurs, seem to indicate perfectly the character of the vein, which before the intrusion of the felsitic dike was more simple than we now find it. My conception of the Imperial vein is that a great fissure formed in this mountain range; that at the time this disruption occurred the hanging wall side of the fault slipped downward, causing a further fissuring and crushing of the rocks on that side of the fault. It is a notable fact that all the branches or spurs of this vein occur in the hanging wall country and are directly connected with the main fissure. This idea is still further substantiated by the additional fact that all, or nearly all, the crushing and grinding adjacent to the fault plane has occurred on the hanging wall side.

Occasionally, in the narrower portions of the vein, a banded structure indicates the probability that the ore now fills what was at one time an open crevice, which slowly filled with ore by precipitation from the mineral waters passing along the fault plane.

At one point on the course of the vein, where it is joined by one of the branching spurs, the felsitic dike has intersected the smaller vein. The occurrence is plainly seen in a cut made at this place, where rich ore was found.

THE ORE.

Although the Imperial vein is a fissure of great length and depth, all the material that is included between the porphyritic walls is not pay The ore occurs in shoots of greater or less extent, the same as in any other vein. The gangue is chiefly quartz, having a pearly luster resembling in appearance some light grayish lead carbonate at a casual glance. Accompanying the quartz, though in minor quantities, are baryta, calcite, and black manganese oxide. The value of the ore lies almost wholly in its silver contents, which occur as chloride and sulphide (argentite) accompanying pyrites, chalcopyrite, and iron oxides. ́ The silver sometimes occurs with copper glance in small bunches in solid masses of lead carbonate. Such ores are very high grade. In one of the branches gold is found with only a small percentage of silver, the reverse condition, however, usually obtains. The silver frequently is found in the same shoots with the base ores and in quartz without any intimate association with either lead, copper, or iron. The galena is sometimes very low grade, carrying only 4 ounces per ton in silver. In one shoot the lead carbonate contains over 200 ounces. It is a notable fact that no good ore is found in quantity without copper in some form, either as sulphide (glance) or carbonate. Chloride of silver is also found associated with iron and manganese, without copper or lead.

THE CLAIMS ON THE VEIN.

There are six lode claims located on the Imperial vein, on all of which considerable work has been done. Beginning at the east end, the vein shows itself on the mountain side close down to the desert wash and not far distant from the basalt flow on this side of the range.

The most easterly claim is called the Sampson, and from it has been shipped some rich ore, the claim producing the highest grade ore, I am told, of any mine on the vein. This claim is joined on the westward by the Morning Star, a deep cañon separating them. From the bottom of this cañon it is 800 feet to the summit of the mine, 1,500 feet farther west. The Morning Star Mine has been quite extensively opened by tunnels and shafts, but for several years past assessment work only has been done, as the ore which was found was too low grade to make shipping profitable.

The Meteor, Mammoth Chief, and Desert Queen succeed each other, respectively, going west. On the Mammoth Chief and Meteor, a great deal of work has been done; and it is claimed ore was shipped approximating $40,000 gross value. At any rate the owners have developed their claims and made a good living at the expense of the ore thus shipped from the vein. On the Meteor a shaft has been sunk a depth of 100 feet, at the bottom of which a drift 40 feet in length has been cut along the vein on an ore shoot which was followed down from the surface. At another point on this claim a shaft of 65 feet in depth has been sunk in ore. A drift at the bottom of this shaft is also in ore, 8 feet of which is exposed and the foot wall not yet reached. The ore at this point is said to average 30 ounces. I was told that average of the ore throughout the mine was about 25 ounces, ranging from 12 to 75 ounces, and occasionally much more. Numerous cuts, shafts, and drifts, some of them of considerable size, have been made

along the vein on the Meteor and Mammoth Chief for a distance of 800 feet, and although these workings are not connected they have the apOne fact is very evident from pearance of being on one shoot of ore. an examination of the mine, and it is one of considerable importance. It is, that the ore is of better grade and occurs in greater quantity in the vicinity of the felsitic dike, which, though undoubtedly later than the vein itself, seems to have enriched the ore very materially. The largest shoot of ore I saw has formed very close to the point of intersection of the felsitic dike with the main vein. On the Desert Queen a long tunnel and several crosscuts have exposed ore bodies, some of which contained upwards of 200 ounces silver per ton.

The Imperial lode is one of the most promising veins of which I have any knowledge, but it requires considerable capital to properly and systematically open it. The rock is extremely hard, and the lack of wood and water are drawbacks which prevent the owners from working the mine as it should be worked. It would be difficult to find a vein offering greater natural advantages than are found here, excepting as to wood and water, both of which are obtainable under the usual conditions attending that problem on the desert. Water can be found in the dry lake 34 miles distant by road, and 1,160 feet below the level of the cañons which cut the vein.

Coal may be delivered at Lavic Station, 5 miles from the lake, for about $9 or $10 a ton. The difficulties are no greater than at Calico, where they seem to have been overcome quite easily. Tunnels may be run in on the vein, getting average backs of about 350 feet above the bottom of the cañons.

Should ever this great vein be worked on a larger scale with abundant capital, a tunnel started at the lake will cut the vein at an average depth of 1,500 feet. Such a tunnel would probably be about 12,000 feet in length. The ore shoots seem to have an average width of about 5 feet as far as exposed, and none of the workings in ore have ever reached the bottom of a shoot. It is one of the most imposing looking veins I ever saw. On the Desert Queen the soft hanging wall has been eroded, leaving the vein standing exposed for fully 80 feet in height.

THE TIPTOP MINE.

About 4,000 feet south from the Imperial lode there is a mine of unusual character and interest, called the Tiptop. Originally a silver mine, it is now producing a high-grade copper ore, which is being shipped to Swansea, Wales.

The Tiptop was discovered in 1890, by the strong outcrop of an ore shoot. The country rock on both sides of the vein is quartz porphyry, The ore occurs along a similar to that inclosing the Imperial lode. fault plane, or rather a series of parallel faults, as the result of substitution of ore for the original rock. The faulting of the rocks has resulted in an extensive crushing and breaking up of the porphyry along the line of fracture, exposing large surfaces of rock, thus faciliAs mentioned above, the faulting tating the deposition of mineral. seems to have consisted of several fractures, nearly or quite parallel, between which the rock was crushed or ground to powder. In places this ore body would seem to possess well-defined walls, but moving in either direction along the strike of this zone the "wall" proves to be

simply a faulting plane, beyond which ore again occurs. The result of these parallel fractures is to give to the deposit an appearance of banded structure, like that sometimes noticed in simple fissure veins. This apparently banded structure is entirely due to the planes of dis placement.

Doubtless this faulting extends to great depth, though the mineralization is not continuous along the surface for more than 150 feet. At some distance, however, and in line with the strike of the displacement, other ore bodies appear. The ore body where the discovery was made is heavily mineralized with iron oxides, of red, yellow, and black colors. Much of the original rock has become silicified and bleached to snowy whiteness in the lower part of the deposit, but such masses contain only finely disseminated iron pyrites, low grade in silver. The once sulphuretted ores are so thoroughly oxidized in this surface deposit that they are very porous.

The ores carry on an average about 30 ounces of silver, and for the, most part are very free-milling. At the time of my visit an estimate of this silver ore on the dump and in the mine placed its value at, approximately, $20,000. In one portion of this rather remarkable ore deposit considerable quantities of native sulphur occur, associated with a brownish iron oxide and silicious gangue material. As depth is attained the oxidation is less marked, and at 80 feet has apparently given place entirely to sulphuretted ores and silicious rock, low in silver.

run under the silver ore shoot from the lower levels of the mine, that oxidized ore will be found at that level, but it will be interesting to know what sort of ore may be found there. Indications of copper on the surface are very slight. In a few places stains and thin seams of copper carbonates occur in the fracture joints of the country rock, but there is nothing to lead one to believe that ore lies beneath that will bear shipment to Europe and return a handsome profit to the owners of the mine, yet such is the case.

THE GLADSTONE GOLD MINE.

Less than a mile from the Tiptop, in a northwestern direction, is another property, the Gladstone, locally known as Halberg's Gold Mine. It was located several years ago, and after some development was practically abandoned, but afterwards came into the hands of the present owners, who have developed the ground quite extensively, built a long tramway and ore bins, and established a camp.

Nothing was being done at the time of my visit. The mine is something of a curiosity geologically and mineralogically. The ore body, for there is only one of any consequence developed, occurs in the gray quartz porphyry common to the region. A fault has also occurred here, fracturing the country rock in a manner similar to that in the Tiptop, excepting that here there is but a single, simple fault. The ore body consists of a mass of crushed and broken country rock, portions of which still show distinctly the original porphyritic structure. Generally speaking, however, the original rock has undergone an extreme metamorphosis, resulting, in most cases, in more or less complete mineralogical and physical changes. The porphyry has, by gradual replacement, been changed to solid ore, or been silicified to a dense quartzose, sometimes jaspery, rock. Kaolinization of the feldspars has also taken place. As to the origin of these deposits there seems to be little reason to doubt that the ore was deposited by percolating waters, which derived their contents from the neighboring eruptive rocks. These solutions were carried into the fault plane, and reaching the great chamber or crushed mass, found conditions of a superior nature for the precipitation of the minerals they contained. In the pulverized or finely crushed portions the ore deposition has been most complete, entirely replacing the original rock, while in the brecciated portions the ore occurs as incrustations, filling the smaller interstices, but sometimes penetrating the rock fragments themselves.

The ore body is something over 200 feet in length and 30 feet or more in width at the widest part, but thinning out rather irregularly toward the ends and also downward.

Doubtless it at one time extended some distance upward, but that portion has been eroded. Along the plane of the fault the line of demarkation between ore and porphyry is very distinct, as the two bear not the slightest resemblance, but at the outer edges of the deposit no such line can be discovered. The mineral gradually disappears, leaving only a brecciated mass of whitish rock, which graduates into the normal porphyry. The brecciated condition of the mass is made more plain by the variety of color assumed by the angular fragments. They are various shades of green, retl, white, and brown, or yellow, caused by copper carbonates and iron oxides.

Though the original condition of the ore was doubtless sulphide, it now contains, as the result of oxidation, hematite, limonite, magnetite, malachite, azurite, chrysocolla, cerussite, wulfenite, chloride of silver, manganese oxide, and metallic gold. The value of the ore lies principally in the gold contained, though in one portion of the ore body, near ts eastern end, rich chloride of silver ore is found, with but little gold. The physical appearance of the ore is no criterion of its gold contents, as two pieces, with identically the same characteristics, will differ widely in value. One may contain $2 or $3 in gold, the other several hundred. Should ever a mill be erected in the district, this ore can be worked to a profit, though this single ore body will alone scarcely justify the construction of a mill.

On the south side of this fissure or slip is a vein which runs nearly parallel with the chambered vein_above described. This vein can be traced for several thousand feet. In character the ore is similar to that found in the Imperial lode. Assays running over $200 in gold have been obtained from this ore, and $50 assays are not uncommon. The vein is quite small, ranging from a mere seam to 2 feet. Scarcely any development has been done on this vein, though it promises better results than the large "vein chamber."

The developments on the Gladstone consist of a shaft 60 feet deep. The first level is cut at a depth of 30 feet from the surface, where drifts have been run for a distance of 30 feet each way from the shaft, on the course of the vein, and a crosscut, 28 feet north. East of this, a 15-foot shaft has been sunk in a good sized cut.. A large open cut, 100 feet long, has exposed the upper portion of the ore deposit perfectly. Other superficial work has been done at various points along the vein. A tramway of 1,700 feet has been constructed from the mine to the bottom of an adjacent cañon.

OTHER CLAIMS.

In the vicinity of the mines described in this district are numerous other claims, some of them having considerable development, but all lying idle at the time of my visit. One claim has an 80-foot tunnel, and shows some lead and silver ore of good grade. This claim is patented.

THE ALVORD MINES.

Twenty-three miles northeast from Daggett are the Alvord Mines. The property has changed hands several times, but is now owned by a party of Pasadena capitalists, who have under consideration the reconstruction of their mill, which was burned in September, 1891.

The property consists of six full claims located on one mineral-bearing zone. The strike of the belt is a few degrees south of west. The mine is well equipped. The company also owns a 'millsite at Camp Cady, on the Mojave River, 9 miles distant from the mines, and valuable water rights at Paradise Springs, 11 miles northwest from the mines, and a spring about 1 miles east of the camp, which is used for camp purposes only.

The mines lie along a broad zone or belt of crystallized carbonate of lime (calcite), which may be seen for many miles traversing the darkcolored inclosing rocks. A huge dike of porphyritic rock cuts across

this belt at an angle approaching 90°. The principal mineralization of the lode occurs east of this dike.

The country rock is described by F. R. Burnham, E.M., formerly the Superintendent, in his report on the property to the company, as rock more or less schistose in character, through which, at frequent intervals, are intruded eruptive dikes. At the east end of the belt is an accumulation of tufa and basalt. The belt dips south at an angle of 75°. The mineralized portion of this lode extends from the porphyry dike east through three full claims, disappearing finally beneath the eruptive rock and desert wash. The dominant point on the lode is 550 feet above the base of the hill.

The entire lode is gold-bearing, some of the iron rock being extremely rich; gold also occurs in the calcite, though it is usually of a lower grade than where accompanied by the iron. Iron sulphide containing gold has been discovered, indicating plainly the origin of the slag-like iron ores and limonite found on the surface.

To Mr. Burnham's report I am also indebted for information concerning the value of the rock, tonnage, and bullion output to date. He has given arbitrary figures for shipments aggregating $37,000, and an estimate on $13,000 more, making a total of $50,000. This ore was milled mostly at the Camp Cady mill and at Hawley's mill.

An arrastra was used in the early history of the mine. The average assays made on a ten days' mill run just prior to the burning of the mill returned $12 75 per ton. Tailings, during the same period, averaged $1 25. Bullion produced, $1,430.. It was found very difficult to sort the ore, though it varied constantly in value from $2 to $20 per ton. About 90 per cent of the assay value, it is claimed, was saved in the mill. In looking through a daily record of assays made in July and August, 1891, I find them to range from a trace to as high as $1,750, most of them running from $6 to $18. Mr. Burnham figures 184,000 tons of mill rock in sight, including all grades, besides large amounts presumed to be available, but not blocked out for stoping. The value of the ore is placed at $5 to $6 throughout.

The cost of milling this ore is placed at $2 50, and mining at 50 cents in large stopes. Should the company now controlling the Alvord Mines determine to rebuild their mill it will doubtless again become a bullion producer.

ORO GRANDE DISTRICT.

The Oro Grande Mining District is located immediately east of the It is comSouthern California Railroad, at the town of Oro Grande. monly supposed to embrace all the mines for some miles around, though, in fact each group of mines or hills has been given a separate name, but as these so-called districts are mostly without organization, all the claims and mines will be considered under one head.

The geology of the district about Oro Grande is complex, the forma tions being uplifted, greatly faulted, and broken, besides the intrusion of dikes of felsitic rock, diorite, and quartz porphyry. I had not sufficient time at my disposal when at Oro Grande to study out the somewhat intricate geological problem, and will describe the region in general

terms.

Commencing at the town of Oro Grande, which stands on the bank of the Mojave River, the country rises in a gentle slope toward the hill half a mile distant; gently rolling hills are reached, which in turn give

place to more rugged masses, and finally to a rough mountainous area, the hillsides being almost precipitous. The lowlying country about the base of the hills is mostly made up of schistose micaceous rocks, a quartzose mica schist predominating. The first hills of any consequence are eruptive, mostly a light-greenish felsite and a coarse-grained porphyritic rock. Beyond are prominent hills of a dense, hard quartzite resting upon a crystalline limestone, the highest hills being made up of practically the same materials (quartzite and limestone), in part schistose with some mica schist, jasper, and many intrusive dikes of all the previously mentioned eruptives, prominent among them being diorite of dark-green color.

THE EMBODY MINE.

Within half a mile of the town, and on a lower spur or ridge that makes down from the hills, is located the Embody Mine, which, during the excitement at this locality in 1890, attracted considerable attention. The gold-bearing material is quartzose, micaceous rock of somewhat friable character. The deposit, as I may term it, has the appearance of being an impregnation without definite form.

Were it not for the fact that the shoot of gold rock makes across the strike of the schists, it would resemble some bedded deposits found at the Homestake, Black Hills, South Dakota, where micaceous schists have been silicified and hornblende schists metamorphosed to chloritic schists, the whole carrying gold across a broad zone 1,600 feet in width and 6,000 feet in length. The gold occurs in shoots or vein-like zones, without defining lines of any character. At the Embody Mine, too, little development has been done to make any positive prediction as to the future of the mine. The formation strikes northeast and southwest, and dips 70° southeast.

The country is somewhat broken up, but no considerable masses of shattered rock were observed. The croppings are quite heavily stained with iron oxides of brown and red shades, and this mineralization can be traced some distance. Two shafts, one nearly 100 feet deep, the other about 30 feet, have been sunk on the deposit, exposing rocks of uniform character, all carrying some gold. The width of the gold-bearing zone is undetermined, but it is thought to be from 6 to 20 feet.

As far as I learned, a "mill-run" had never been made on the rock from this mine. Mining operations had been stopped and the property involved in some sort of dispute. The value of the rock was given to me as $8 or $10 per ton.

THE CARBONATE MINE.

The principal mine of this district, and the one which gave the camp its fame, is the Carbonate Mine. It was discovered by a man named Collins, who was working in a lime quarry near by. Collins found croppings of ore-limonite and manganese-containing silver. developed the property somewhat, but it finally passed into other hands, and is now owned by a Los Angeles company, which has opened the mine quite extensively.

He

The formation which incloses the vein has a general trend northeast and southwest, the dip at the main workings being not over 20°. Here an inclined shaft has been sunk to a depth of 225 feet on the vein. At the bottom the shaft has attained a vertical depth of about 100 feet.