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to their ultimate value. A small mill has been forwarded to the district, and a more thorough trial of the ores will no doubt soon be had. These mines lie in the midst of a hideous desert, and unless excessively rich can possess no present value, the country for more than fifty miles in every direction being almost wholly devoid of wood, water, and grass.

In the Pueblo mountains, sixty miles northeast of Black Rock, a district was organized, and many ledges located five years ago. A small water mill erected there, and afterwards burnt by the Indians, has not since been rebuilt, nor have the mines showing fine surface indications been at all opened; wherefore, little or nothing is known as to their real character. The ores are an argentiferous galena, abounding in both silver aud lead, and may possibly require reduction by smelting. If so, this mode could be adopted with a fair prospect of success, as wood and water are tolerably plentiful in the neighborhood of the mines, there being also much good hay and farming land in the extensive valley adjacent.

In Humboldt county proper mining operations, as well as population, have diminished considerably during the past two years, nor will the shipments of bullion this year equal those of either of the three years immediately preceding The work now being done, however, is more thorough, being confined to a smaller number of ledges than before, and will no doubt prove more satisfactory in its results.

In Churchill county there are three districts that have attracted some notice, because of the supposed valuable ledges they contained. These are severally named the Silver Hill, the Mountain Well, and the Clan Alpine, and to them most of the work performed in the county has been confined. There are in this county four quartz mills, carrying 55 stamps, and having a driving power equal to that of 165 horses. The total cost of these mills was $395,000. Three of them are in Mountain Well, and one not quite finished in Clan Alpine district. They have produced but a few thousand dollars' worth of bullion all told, none of them having been able to run for more than a few days at a time, from an insufficient supply of pay ore, but few of the ledges here having been opened to even the superficial depths common to most other districts. In the higher strata of some of them small aggregations of very rich ores have been found, and the chances favor the supposition that when properly developed they will afford enough ore to keep the present and perhaps additional mills running. Very few additional mills, however, can ever be operated in the western half of the county, owing to the limited supply of wood and water.

The Reese River region, embracing within its boundaries the extensive counties of Lander and Nye, covers more than one-half of the entire State of Nevada. The geology of this region differs somewhat from that in the western part of the State, limestone of the silurian epoch abounding here, and other sedimentary rocks being more common. Carboniferous signs are also more frequent. The ledges throughout this region are mostly encased in granite or granitic rock, such as gneiss, sienite, &c., in limestone, and the several varieties of slate, a few only being found in rocks of volcanic origin. Most of the large and well-defined veins lie in silurian limestone, a formation highly favorable to the existence of deep-fissured and permanant mines. The lodes about Austin, Lander county, occur wholly in granite, both walls as well as the country rock being of this character. They are for the most part very narrow, varying from six to eighteen inches in width on top, and expanding to two or three feet at the depth of 300 feet, the greatest vertical depth to which any have yet been opened. Besides being narrow, these ledges are apt to suffer much from faults, and occasionally contract to a mere seam of quartz, or disappear altogether. Where these faults have occurred the experienced miner is generally able to place them again sometimes without much labor. Most of these veins run in a northerly and southerly direction, and stand at an angle varying from 45 to 60 degrees,

very few of them having a more vertical position. Owing to the firmness of their walls very little timbering is required, though their extreme narrowness compels the performance of much dead-work in the course of their development. There are 36 steam hoisting works employed on the mines in the neighborhood of Austin. They are mostly of small capacity, from 20 to 25 horse power, but owing to the small amount of ore as well as water required to be raised they will meet all the demands for hoisting until the mines reach a depth of four or five hundred feet. The ores in this vicinity are the sulphurets and the red antimonial sulphurets of silver, though in the top rock, and in some instancesfor a considerable distance beneath the surface, these have been changed by decomposition into chlorides, bromides, and iodides of silver. These ores, being impregnated with antimony and arsenic, all require roasting. Though small in quantity, not more than 35 or 40 tons being raised daily from all the mines in the Reese River district proper, these ores are extremely rich, yielding by mill process from one to two hundred dollars per ton, the average yield being nearly one hundred and fifty dollars, while selected lots often go as high as four or five hundred dollars. There are in the several districts immediately around Austin seventeen steam mills, carrying nearly two hundred stamps, and capable of crushing and amalgamating one hundred and fifty tons of ore daily. Owing, however, to an inadequate supply of ore not one-quarter of these mills have been kept running during the past year, nor is even so large a proportion now in operation. With a more thorough exploration of the veins, however, upon which they are dependent for their supplies of ore, it is thought an additional number will soon be running, and that all will be able to do so in the course of a year or a year and a half at the furthest. The cost of reducing ores about Austin is now $15 per ton; the expense of raising them is about $15 per ton.

In several of the outside districts mines of not only undoubted, but very great value, some of them to all appearance not inferior to the Comstock ledge, have been discovered within the past two years. The most remarkable of these is the ledge known as the High Bridge, in the Philadelphia district, seventy-five miles south-southeast of Austin, the entire mass of vein-stone in which, varying from five to fifteen feet in thickness, pays under the stamps over one hundred and fifty dollars per ton. A small five stamp mill erected at the place and running on this ore turns out over a thousand dollars worth of bullion per day, the ore taken indiscriminately and worked in a very imperfect manner yielding over two hundred dollars per ton. This is beyond dispute an immensely valuable deposit of silver, and it is the intention of the companies claiming it to erect one or more large mills for reducing the ore the coming summer. In the Northumberland, Hot Creek, Danville, Reveille, and Pahrangat districts, all situated to the east and southeast of the Philadelphia district, many ledges of great promise have been discovered within the past year, some of them to all appearance quite as good as the High Bridge, showing beyond peradventure that a great silver producing region exists in this part of the State. Several small mills have been aken into this section, and many more of large capacity will soon follow, and it will be cause for surprise if the annual bullion product of the Reese River region, now about $1,000,000, is not more than doubled within the next two years These districts, as also the Murphy ledge, fifty miles south of Austin, a decidedly valuable mine, are all in Nye county, which contains a number of districts abounding in argentiferous lodes of great magnitude and prospective value.

The Reese River region contains thirty-two mines, of which twenty-two are in Lander and ten in Nye counties. These carry three hundred and ten stamps, have a capacity of four hundred and twenty-five horse-power, and cost $1,500,000, the expense of erecting mills here being much greater (owing to cost of freight and lumber) than in the western part of the State.

Oregon. The yield of the mines in this State the present year will not exceed $2,000,000, nearly the whole being the product of placer diggings, and H. Ex. Doc. 29–9

mostly taken from the mines on John Day river and its tributaries. Several auriferous veins have been worked with arrastras for a number of years past at Althouse and State creek, in southern Oregon, paying, for the means invested, very largely; and there is no doubt but these mines, with ample facilities for reducing the ores, would turn out considerable amounts of bullion annually. Some attempts were made during the present year to work the quartz lodes, of which there are quite a good many in the Santian district, situated in the Cascade mountains, but the results obtained have not thus far been encouraging.

Washington Territory. As in the State of Oregon so in this Territory, the only class of mines that have yet proved productive are the placer diggings, of which there is here a considerable extent, the best paying mines heretofore discovered being those about Fort Colville and in the Pend d'Oreille country, the Kootenai mines and those near the Big Bend of the Columbia, generally spoken of as being in Washington Territory, being in fact in British Columbia. The product for the present year from this quarter may be set down at about $1,000,000, though this must be understood as embracing the yield of the lastmentioned districts, that of Washington alone not reaching one quarter this

amount.

Utah.-This Territory is known to abound in many of the useful and, it is believed, also in the precious metals. Coal of fair quality and in considerable quantities has been found in various parts of the Territory, and both lead and iron have been produced for many years past by the Mormons living in the southern counties. That so little is known of its wealth in the precious metals is owing to the fact that the leaders of this people discouraged the searching after them, it being contrary to the policy of the church to have its subjects engage in mining pursuits, wherefore but little was known of the mineral resources of Utah until the soldiers stationed at Salt lake brought them to light. No placer mines of any extent have yet been found in this Territory, but a number of large lodes heavily charged with argentiferous galena have been opened at Rush valley, a short distance southwest of Salt Lake City, and, being tested by the smelting process, proved rich in both lead and silver. A number of furnaces were erected here two years ago, since which they have been kept part of the time in operation, and with suitable appliances it is thought a considerable amount of silver bullion might be produced from these mines. With the influx of gentile population Utah is destined to be thoroughly explored, and whatever mineral riches it may contain to be brought to light; and we may reasonably look for some important discoveries to follow in that section before long. At Egan cañon several rich silver-bearing lodes were located over two years ago. Three mills have since been put up at this point, two of which have produced quite a large amount of bullion.

The principal silver-bearing lode at this point, known as the Gilligan Ledge, has been tested to the depth of three hundred feet, and is considered to contain one of the richest veins in the State of Nevada. It has a width of eight feet, and has produced by ordinary process of mill-working at the rate of $345 per ton, for fifty tons. The average of ore rates at something over $100 per ton.

This valuable mine belonged, until recently, to a San Francisco company, consisting of seven private individuals, who worked it on their own account, under the superintendency of Mr. John O'Dougherty, who, by a careful system of operations, not only developed the mine, but built a five-stamp mill without expense to the company. It is one of the few mines in the county which has paid its own expenses from the first crushing of the ores.

During the past summer the mill has been idle owing to the departure of the superintendent, who went east for the purpose of procuring capital sufficient to erect a mill of the first class, with capacity to work all the ores that can be obtained from the ledge.

The Steptoe Company, of New York, have also. large interests here, and own

a number of ledges, which, however, have not yet been developed sufficiently to furnish an absolute test of their value.

A consolidation has been formed between the Social or Gilligan company and the Steptoe, which will probably result in mutual benefits. The Steptoe company have capital, and have already made provision for the erection of a large mill; the Social company have a developed ledge already tested, and unquestionably productive.

This consolidation owns, in addition, some fine copper mines on the line of the proposed trans-continental railway. No work of any importance has yet been done upon them.

Egan cañon is situated one hundred and sixty miles from Salt Lake City, and already forms the nucleus of quite a thriving little mining town. The overland stage and telegraph lines pass through this cañon on the route to Salt Lake. Preparations are being made for the vigorous working of all the valuable mines in this district, and it is believed they will yield profitable results. during the coming summer.

Montana.-The productive mines in this Territory have thus far mostly consisted of placer diggings, the principal of which, being situated east of the summit of the Rocky mountains, are without the province of these reports. The amount of gold dust taken out the present year has been large, but in the absence of any authentic data no accurate computation can be made thereof. According to the public press of that region it will reach the sum of $15,000,000, though this is probably a rather high estimate. During the past summer a large number of quartz lodes have been taken up and opened, some ten or fifteen mills, varying in capacity from five to twenty stamps, having meantime been brought in and some of them gotten in operation. The quartz is easily worked, and yields largely, the product being chiefly gold. All the goods and machinery destined for the eastern part of Montana are freighted up the Missouri or across the plains. Most of the gold dust and bullion produced in this Territory is sent cast, very little of it reaching California. Those best acquainted with the country have a high opinion of its mineral resources, and believe it will in a few years rival Idaho and Nevada, if it do not surpass them, in its product of the precious metals.

Idaho. The product of the placer mines in this Territory has been gradually diminishing for the past two years, though this falling off, if it have not already been, will soon be more than made up by the yield of the quartz mines, which are beginning to be worked quite extensively. The product from both sources the present year will probably not fall short of $10,000,000, some estimating it much higher. It should be observed that there are no means of arriving at accurate estimates of the precious metals taken out in this Territory, many of the millmen not caring to make known the results of their operations, and large quantities of dust being brought out of the country in private hands. Of the total sum produced, from one-fourth to one-fifth is taken from the placers, of which some virgin diggings of considerable extent and value have been found the past summer; and as ditches have been constructed for bringing water into the mines on quite an extensive scale, and hydraulic washing is being introduced wherever practicable, the probability is that the present quota from this source will be kept up for some time to come. There are now twenty-four quartz mills completed and running in this Territory, with eight others in course of erection. They carry a total of nearly four hundred stamps, cost in the aggregate $1,000,000, and have a united capacity equal to five hundred horses. Besides these mills, about one-fourth of which are driven by water, there are a large number of arrastras running in the Territory, the most of which are also propelled by water. Of the quartz mills eight are supplied with one hundred and thirty-four stamps, are situate in Atturas county, ten in the Owyhee district, and the balance in the counties adjacent; the whole being in the southern

section of the Territory. The Poorman ledge, so-called, situate in the Owyhee district, is, perhaps, for its size, the richest deposit of silver ores ever discovered, immense masses of pure sulphurets, and even pieces of virgin silver weighing many pounds, having been extracted from it. Unfortunately, it is now closed up by litigation, and has not for several months produced any bullion. There are also several other rich silver-bearing claims in this vicinity, though the mines of Idaho consist mainly of auriferous quartz, of which there are great quantities that will yield by the most cheap and expeditious modes of working from $20 to $30 to the ton. Considering the abundance of these ores, the facility with which they can be treated, and the ample supplies of wood and water in the vicinity of the principal mines, it may fairly be concluded that the bullion product of Idaho will in a few years be more than doubled, and that the yield of her mines will hereafter be steady and rapid.

REPORT OF DR. A. BLATCHLY, MINING ENGINEER, TO J. ROSS BROWNE, SPECIAL COMMISSIONER FOR THE COLLECTION OF MINING STATISTICS.

SOUTHEASTERN NEVADA.

This portion of the State of Nevada, owing to the hostility of the Indians, was almost totally unexplored until last spring. About that time, observing that the Indians in the vicinity of the mining towns were able to feed and clothe themselves much better than those who lived out in the mountains, they changed their tactics, and instead of opposing exploration, offered every facility in their power to promote it, and nearly all of the mineral discoveries in this region have been made by means of their assistance.

The volcanic rocks which so greatly predominate in the northern and western portions of the State are not found to any considerable extent in the southeastern. Hence, there is a much larger amount of metalliferous country accessible in the same compass than in other portions of the State.

These volcanic rocks are the despair of the experienced prospector, for he knows full well that they enclose neither metal nor mineral of any value in this country, and where they abound water is generally wanting. Their geological age is comparatively recent, and undoubtedly more than one-half of the metalliferous veins in the State of Nevada are covered by rocks of volcanic origin. In this part of the State limestone predominates, but granite, slate, and sandstone occur at intervals. All of these rocks enclose valuable metalliferous veins in equal abundance.

This limestone affords better exemplifications of the geology of the sedimentary rocks than any other sections west of the Rocky mountains yet discovered. With the slight and hasty examinations already made, the silurian, triassic, and jurassic have been positively determined, and considerable evidence has been found of the existence of the Devonian and carboniferous epochs. In the territory of the United States no finer field exists for the researches of a geologist. Trap dykes of porphyry and green-stone are abundant, and enormous veins of quartzite of three or four hundred feet in thickness can be traced for forty or fifty miles.

Compared with the veins found in California, Oregon, Idaho, and the other portions of Nevada, the metalliferous veins in this portion of the State are large, and usually can be traced on the surface for a long distance.

As this country has been but recently explored, all of the ores so far obtained have been taken from near the surface; consequently, only surface ores have been obtained. These consist of chloride and carbonate of silver, associated with small amounts of native silver, and nearly all contain gold. Besides the precious metals, ores of copper, lead, iron, antimony, and arsenic are abundant, and when railroads traverse the country, will be of great value.

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