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The rocks of Yellow Pine as well as those composing the country north of it have been disturbed principally by volcanic agencies; and in places they have been metamorphosed.
The limestone, which is very often capped by metamorphic conglomerates, has been penetrated by eruptive rocks of various character, which have overflowed both. In places they resemble a very porous lava, and form vertical bluffs often showing large-sized cavities. Belts of laminated bluish limestone, full of minute crystals of iron pyrites, almost resembling a slate, intersect at various angles the general strike and dip of the blackish compact siliceous limestone, which is the predominant, and at the same time the vein-bearing, rock of the district. Subordinate to it, ferruginous dolomite is found. The gangue rock is generally calc spar, with quartz, calcite, anhydrite, and brownspar; with them occur the following ores: galena, with a variable percentage in silver. It occurs coarsely crystallized, poor in silver, and finely crystalline, almost granular, carrying a larger percentage of silver. Accompanying this, pyrites of iron and copper in all stages of decomposition, and zinc and antimony blende are found, but the latter not in sufficient quantities to be a material detriment to the ores.
The veins of the district are of various width, ranging from 2 to 30 feet. Near the surface they are generally irregular; the walls can in many instances not be defined. The disturbances above named, aided by the speedy decomposition of the rocks carrying iron pyrites, are the cause of the frequent recurrence of so-called blind ledges, to which I attribute the fact that up to the present time not more metalliferous veins have been discovered.
Near the surface the generality of the veins represent masses of large ore-boulders and country rock thrown together, and in places cemented by a calcareous earthy mass, which are often the only indications of the existence of a vein in the vicinity. Regularity becomes rapidly appar ent, however, as depth is attained; the walls still broken in places begin to show themselves, and the vein partakes of a more uniform character. The ore near the surface exists in detached bodies of various sizes distributed through the entire vein, penetrating sometimes the hanging wall; but as explorations proceed in depth, these bodies run generally into narrower and wider seams lying close to, and running parallel with, the foot-wall, and containing ore more concentrated and richer.
Few mittes have been explored as yet, but their general appearance, and the occurrence of such large detached solid ore boulders as are often met with on the hill-sides and in the washes, lead me to expect the discovery of wide veins and large ore-deposits in the future. At present the only noteworthy ones are the Comet, Excelsior, War Eagle, Red Warrior, and Nut Pine veins; and as it is only twelve months since mining has been taken up again in the district, the work done on these is very limited. This is the more to be expected as a great many obsta cles have to be overcome by the first settlers in all of these districts surrounded by deserts.
Besides several private individuals owning and working veins, the Silver State Mining Company and the Excelsior Mining Company are operating in the district. I shall describe two mines, one of each company, and of different character, and these will give a good idea of the character of all those discovered so far.
The Comet mine is owned by the Silver State Mining Company, who have located a town-site-Crystal City, named after the springs of the immediate vicinity-on the old Salt Lake route, about three and one-half miles from Mesquit Valley, and in the southern portion
of the district. Here several buildings have been erected. About one mile southeast from and 600 feet above Crystal City, on the southwestern outrunners of the Potosi Mountains, at a total elevation of 6,100 feet above the level of the sea, lies the Comet mine, connected by a wide, well-beaten trail with the town-site. It is at present the prominent vein of the district, is very massive, has compact, blackish limestone as underlie and dolomite as overlie. Its course is north 200 west; the dip, from 20° to 30° east. It shows itself along a vertical bluff of over 100 feet, where the foot-wall is plainly discernible, and can be traced for 2,000 feet and more. The hanging wall is not plainly traceable, owing partially to the disturbances which the mountain has suffered, and partially to the advanced state of decomposition and crumbling to which dolomite is subject when exposed to the influence of the weather.
Work was commenced by a cut at the bluff on the western slope of the mountain, which exposed the vein for 30 feet in width and 40 feet in length, presenting a mass of ore and country rock, the former predominating by far. An incline of 40 feet traverses the vein diagonally below this cut; and here horizontal drifts, 70 feet long, have been run on the vein. The lower workings show, the metal to exist in seams and bunches, varying from 4 to 9 feet in width, of solid compact ore, separated by barren bunches of gangue. These bunches and seams of ore at the surface are as likely to yield 5 as 500 tons of ore; there is no regularity observable in their occurrence.
According to the crystalline structure of the galena, the ores are either rich or poor, the coarse being poorer than the fine galena; and the larger the proportion of antimony in the ore, the less the amount of silver. This renders assorting by hand not difficult. A sample of ore, regardless of waste from ore-seams of 6 inches to 11 feet in width, taken along the vein for 336 feet in length, gave 31 per cent. lead and $36 09 silver per ton, and no gold. The same sample, as it would be extracted in working on a large scale, yielded 50 per cent. lead and $47 19 silver per ton.
There are three classes of ore which I sampled, observing their proportion to one another as they exist in the vein, in order to get at the actual merit of the whole, viz:
1. The coarse galena, accompanied by antimonite and blende, taken from a bunch 6 feet wide in the incline, which in working the mine will yield probably one-half of the entire ore-bulk of the vein, gave 67 per cent. lead and $43 79 silver per ton.
2. The finer, closer crystallized galena, as it occurs in the lower works and southward from the cut, carrying lead-ochre, pyromorphite, and minnte crystals of polybasite, and which forms about one-third of the bulk of the ore of the entire vein, one sample yielded 50 per cent. lead and $60 02 silver per ton; another sample yielded 54 per cent. lead and $64 75 silver per ton; and a sample taken from a pocket containing probably 800 pounds of ore yielded 42 per cent. lead and $127 19 silver per ton.
3. The fine-grained galena carrying much antimony, of a fibrous texture, as it occurs in small seams, intersecting nearly all the ore-seams in the mine, and which may be called one-sixth of the ore-bulk of the vein, gave 21.3 per cent. lead and $33 06 silver.
Taking these proportions of the three classes, the average would be an ore of 543 per cent. lead and $48 11 silver, as it can be taken forthwith from the mine. This, however, may be improved by assorting in mining (causing a probable loss of 15 per cent. of the ore) to 65 per cent. lead and $60 silver per ton.
The entire excavations made at the mine represent 8,313 cubic feet, and as the work now stands to view two-fifths ore-yield of the abovestipulated quality (from 55 to 64 per cent. lead and $45 to $60 silver value) to three-fifth waste, may be depended upon.
The company have extracted 95 tons of selected ore now piled on the dump, of 63 per cent. lead and $56 54 silver per ton, and about 200 tons of ore, which, when assorted, will yield probably 100 tons of the above average. The company had one ton of selected ore experimented upon by Mr. Taylor at San Francisco, giving 60 per cent. lead and bullion of $225 silver value per ton, which would represent $135 silver value in the ton of ore.
The Excelsior mine is the property of the Excelsior Company of Los Angeles.. It is situated thirty-five miles by wagon-road in a northerly direction from Crystal City, in the Charlston Mountains, which are a portion of the Mountain Spring Range. The vein has a general northeasterly course, and dips 35° west. It is bounded on the southeast by heavy belts of grayish sandstone, running parallel with the vein, and has a bluish, compact limestone as overly. The vein-matrix is principally brownspar; calespar and quartz occur in places subordinately. The ore is argentiferous galena, accompanied by copper ores. Its elevation is 5,600 feet above sea-level. The outcrop has been followed for 70 feet north and south, stands in bold relief from 2 to 4 feet in width, and carries $75 silver value per ton, combined with 30 per cent. lead. The ore is not as rich in lead, and the character of the vein is entirely different from that of the Comet. It does not carry as much antimony, less blende, and copper takes the place of the iron of the Comet. The vein shows, besides smaller seams, a width of 13 feet of ore lying near and running parallel with the foot-wall, widening and narrowing in places. An assorted sample of this gave 47 per cent. lead and $94 72 silver value perton. The mine has been opened by a horizontal cut of 55 feet in length, with the intention to cut the vein at right angles to its walls; but this has not yet been accomplished. A few tons of good ore have been extracted, and the entire work done looks promising for the future.
The two described veins give the general character of the veins of the district; they all conform to these more or less. Little work has been done so far, and the district has as yet not given any yield, as it is but in its infancy.
The facilities for working the mines are good; most of them can be attacked by tunnels. Iron and copper ores, desirable material for flux in smelting, are plenty in the vicinity; and at Crystal City exists a bed of clay containing no iron, little, if any, lime, and is, therefore, an excellent fire-brick material.
In order to give an approximate idea of the actual worth of the district, I subjoin an estimate of the cost of raising and treating 12 tons of ore, worked and extracted under the present circumstances. Twelve tons of ore can be extracted in twenty-four hours by four men. Taking the above estimated average of $48 11 silver value with 543 per cent. of lead, i. e., the ore unassorted, we have—
A. Cost of mining:
Seven hands in all, at $4
Rough-assorting on dump, at $1.
Timbering, tools, &c., at 75 cents per ton..
Transportation to smelt-works at Crystal City, at $3 per ton...
Total cost equal to $7 09 per ton.
B. Cost of beneficiation:
Extra assorting at the smelting works, (if necessary,) at $1 per
Crushing the ore in a Blake's crusher, at $2 per ton.
Wear and tear of machinery, furnace repairs, at $3 per ton...
Labor, four hands, at $5..
Three cords fuel, at $4..
Stack furnace, 12 tons capacity:
Labor, four hands, at $6..
264 bushels of coal, at 16 cents.
Extra labor at smelting works, four hands, at $4....
Cost of beneficiation, therefore, $15 52 per ton.
If smelting is carried on properly, at least 80 per cent. of the assay value of the lead and 90 per cent. of the silver value ought to be ob tained, representing, therefore, 43.4 per cent. lead and $43 29 silver value. We would have, therefore, from 12 tons—
Therefore, a profit at the mine of $560 64 from 12 tons of ore.
Freight to Los Angeles, at 3 cents per pound.
Assay charges on bullion, tax, etc., 24 per cent., (of 790.35 dol
against value of 5 tons 416 pounds bullion, total, $831 96; leaving a profit of $79 77 from mining and smelting 12 tons of ore.
The above description and estimates show that with economy and energy lucrative mining operations can be carried on in the district, not perhaps at first with such magnificent results as many not acquainted
with the facts which now exist in favor of and against the district would at first suppose, but with sufficient profit to justify investment of capital.
It is quite probable that actual practical demonstration in future may prove my estimate in regard to the representation of the quality and quantity of the ores too low, but I have purposely abstained from all flattery, and, on the contrary, underrated the facts. The wealth is there; the district is new; transportation is very high, but this will be reduced in time; and when smelting is once taken up with only half the energy with which amalgamation was taken in hand by the western people, such districts as Yellow Pine will stand among the foremost in rank.
Tem Piute district is about one hundred miles almost due south of Hamilton; by the road now traveled it is one hundred and forty miles. This road passes by the Current Creek and Blue Eagle Ranch.
The general prospect of mines in this district is very fair, and great confidence in them is felt by the owners. The McKenzie claim, worked by Judge Thompson, has about 150 tons of first-class ore on the dump, and work is still progressing in good earnest. The opening from which ore has been taken during the past season is an open cut nearly 40 feet wide, and now in about 50 feet. The ore on the dump is reported to assay from $100 to $300. A tunnel will be started in from this open cut and then work can go on without hinderance by the weather. The Monroe is sinking an incline; the ledge is 12 to 15 feet wide, with a paystreak of 3 feet. Twenty tons of ore of a quality similar to that of the McKenzie are out. The Amazon is being tested from an open cut. The ore is about the same as in the above-mentioned. It is easily worked, two men taking out a ton and a half in a day. The Rattler shows a high grade of ore, and Judge Thompson intends soon to open it. McMurry is working the Incas and Santa Cruz. All owners of mines are satisfied that at an early day they will be able to make a showing of ore on the dumps sufficient to encourage the erection of a mill to work the supply of ore believed to exist in the mountain. At present, no mill can be reached conveniently. The Crescent Mill is expected to be ready to start up about the 1st of February, 1871. It is a ten-stamp mill situated fifteen miles from the Tem Piute mines, in the direction of Pahranagat. At Ticapoo Springs, eight miles from the mines, there is enough flowing water to drive a twenty-stamp mill, and in the vicinity is plenty of wood-cedar and nut-pine.
Besides the aboved-named, the Savage, Silver Peak, Blue Eagle, Demerara, and several other mines have been opened to a small extent, principally for the purpose of getting enough rich rock out to ship for a test. A vast number of ledges lie entirely idle for want of facilities for reducing the ores.
I have no information as yet in regard to the operations of the Hyko Company, at Pahranagat, during the year, but my impression is that no work of any consequence has been done.
The following are the returns of the mines in Lincoln County during the year ending June 30, 1870. They were kindly furnished me by Mr. N. H. Carlow, the county assessor: