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results. Near to the city are two mill-sites, with reduction works-the larger one belonging to the Cervantes Mining Company-about threefourths of a mile from town, comprising three furnaces, crushers, &c., of thirty tons beneficiating capacity, the whole driven by water-power. Within one-fourth to one-half mile from Lone Pine runs Owen's River, which is navigable for flat-boats at all seasons of the year from Owen's Lake up to Owensville, a distance of sixty-five miles.

The mountains which bound Lone Pine Valley on the west, and which slope very abruptly eastward into Lone Pine and Owen's Valley, are worthy of mention. The most prominent peaks are Mount Whitney, 15,000 feet; Mount Williamson, 14,300 feet, and Mount Tyndall, 14,000 feet high. These mountains abound in timber lands, and furnish water in sufficient quantities for excellent mill-sites. Although timber is abundant, all lumber for building purposes comes, as yet, from a point fifty miles to the northeast of Lone Pine, and is, consequently, still high in price.

Cerro Gordo City, the center of the mining district, is situated about 7,200 feet above the ocean level, and nineteen miles by wagon-road in a southeastern direction from Lone Pine City. Its elevation above Lone Pine is about 2,000 feet. It lies in a deep ravine on the western slope of Inyo Mountain, and has at present about five hundred and fifty inhabitants. The mountains here are almost barren of vegetation, and there is but a limited amount of fuel. Water is very scarce. At present there are but three wells of from 20 to 60 feet in depth, and some water (3 to 4 inches) has been brought in pipes a distance of four and a half miles, which, however, is barely sufficient for home cousumption. This fact has been a great detriment to operations at Cerro Gordo thus far, but in time it can be remedied by sinking more wells, and bringing water from a point nine miles north of the city in pipes or ditches and flumes. There is quite a supply at the locality spoken of, and the enterprise will involve a cost of not more than $80,000.

That portion of the Inyo Mountains in which Cerro Gordo mining district is situated consists of a single chain, having a general northwestern and southeastern course. It is not exactly detached from the Inyo range, but a depression of about 600 feet to the northward separates it apparently, while southward it falls gradually toward Owen's Lake. Its cañons and ravines have a general southwest direction, descending toward Owen's Valley; they are abrupt for about two miles from the mountain summit, but farther south the slope is more gradual, and low hills, for a distance of about two miles, intervene between the steeper parts and the valley. The main bulk of this range, which is called Cerro Gordo, is composed of metamorphic rocks, which contain heavy belts of crystalline and compact limestone, and are intersected by porphyries of various character. The lines of contact are promptly discernible, even where the slates are partly covered over by soil, the latter being mostly ferruginous clay-slates, but sometimes they are calcareous. The lower portion of the southwestern slope, about one and a half miles from Owen's Valley, shows a massive belt of siliceous slates. They run parallel with the main mountain-chain, dip southwest, and seem to be the division line between the sandstone formation of the lowest hills and the metalliferous belt of the mountain above. In this metalliferous belt, limestone is predominant. The veins occur either altogether in it, or as contact-veins. In the former case, the foot-wall of a vein is generally discernible by a clay-seam, forming the division line. The hanging and foot-wall of a vein are in many instances distinguished from one another by the different crystalline structure of the limestone, but

in most cases the walls are compact limestone, showing only here and there signs of a crystalline structure, while the vein-matter is a crystalline limestone. In the second case, that of contact-veins, we have generally slate overlying, quartz, or quartzite predominating as veinmatrix, and compact limestone as foot-wall. The outcrops of these veins are often very bold and massive, but in many instances they have suffered a dislocation sideways, the cause of which is fully explained by the abruptness of the cañons. This is very apt to mislead as to the actual width or dip of a vein, and even as to its location.

The course of the veins is northwest and southeast, with a changeable southwesterly dip, except in the extreme northern portion of the district, where the veins turn more and more to an east and west course, and dip north. The northwest and southeast course is a general rule, but is not exempt from exceptions, as metalliferous cross-courses exist in the district: for instance, the Soledad vein, which strikes the St. Lucas and Abundancia at an angle of 650, and has an almost north and south course, and dips west. Most of the veins dip from 70° to 60° except near the surface, where irregularities are naturally to be expected and are frequently met with. The veins of the district may be divided into two distinct classes, according to their contents, namely: 1. Those which carry mainly argentiferous galena ores; and 2. Those which carry principally copper ores.

The first class have invariably limestone, the second class predomi nantly quartz and quartzite, as vein-matter. The second class are best defined and the more massive of the two, and are also less subject to irregularities near the surface than the first class. They carry the larger amount of precious metal, and are in consequence termed 'silver leads' throughout the district, while the first class are known as 'lead leads.'

Local circumstances have been the cause, that up to the present time but a limited amount of work has been done on the veins, hardly sufficient to realize the actual merits of many of them. The aim of all work done so far has been always to produce in the shortest possible time the largest amount of ore in order to realize, and judicious work, namely, producing and developing at the same time, has been neglected. Every mining district in its infancy is, of course, subject to this, especially if its yield can be made available forthwith, as is and has been the case in Cerro Gordo ever since its discovery.

To facilitate a description of the ores I shall retain the terms in vogue in the district, calling the above first class "galena ores" and the second class "silver ores."

The ores of the district are of various nature and character, the latter undoubtedly attributable to the character of the rock, which forms the main bulk of the vein-matrix, and also to the nature of the rock which occurs in the immediate vicinity of the veins. They are argentiferous galena, (coarse and fine crystallized,) carbonate of lead, argentiferous copper ore, principally as gray copper ore, and iron pyrites in various stages of decomposition.

Subordinately occur antimonial silver ore with traces of speiss-cobalt, silver-copper glance, silver-bearing malachite, azurite, sulphuret of silver, sometimes partly decomposed and mostly free from refractory metals, and native silver, which occurs often in the malachite and azurite.

Gold is found in traces only, and occurs mostly in the northern portion of the district, although some of the veins situated in the extreme south westerly part of the district show it sometimes. Nearly all the veins carry more or less of all the above-named ores, but, as stated

above, the veins bearing limestone as gangue matter have galena pro dominant, accompanied by iron pyrites, which, near the surface, are decomposed to oxides, coloring the entire vein-matter yellowish and red, and entirely veiling its texture. The ore in these veins, as far as can be observed by actual explorations made up to the present time, occurs in nests, pockets, and irregularly shaped deposits, which run generally parallel with and lie very close to the foot-wall of the vein. These vary in width from 1 to 15 feet, and have in several instances been worked to a vertical depth of 40 feet and over 120 feet in length on the strike of the vein, showing no signs of pinching; on the contrary, in two instances, a depth of 150 and 170 feet has been attained, where the iron pyrites are only partially decomposed, and here the silver value has been found unchanged in the ores. The lowest workings of the district have in no instance reached the water-level, and it is impossible to say how the silver value of the ores will hold out where they will be found entirely undecomposed. So far this has not changed at a depth where the accompanying iron ore changed its entire character, and this must lead us to expect a continuation of the silver value of the ores in depth. The galena occurs in various forms, from the coarsely crystallized to the granular and almost solid texture; and although the former theory of the German miners, that the finer and closer the crystals the richer is the ore in silver, is now considered wrong, this has nevertheless been found to be the case in Cerro Gordo. A sample of coarse crystals of galena, from the Union mine, 25 feet below the surface, yielded $84 32 in silver and 67 per cent. of lead, while a similar sample, from the same vein, taken from 60 feet below the surface out of the Santa Maria tunnel, where the accompanying iron pyrites were little, if any, decomposed, gave $91 13 in silver and 58 per cent. of lead. The finely crystallized galena from the Union mine, from about 40 feet below the surface, was found to contain 61 per cent, of lead and $117 53 in silver per ton of ore.

The class of veins bearing quartz as vein-matter and cupriferous silver ores carries galena only subordinately. The ores occur generally in seams from 2 inches to 5 feet wide, and can be followed with some degree of certainty as to duration in depth. They lie generally in or near the center of the vein, wide and narrow at intervals, and when, as is sometimes the case, they hug the hanging wall for some distance, they contain rich ores. But when the entire fissure from wall to wall is filled with ore, it is generally poor in silver and much mixed with veinmatter. In some instances the work done in depth on these veins has proven that the ore improves in quality and quantity as depth on the vein is attained, as, for instance, in the St. Lucas mine. The outerop of this vein shows malachite stains profusely in many places, bearing $7 to $12 per ton in silver; 45 feet below the surface no highly oxidized copper ores are found, and 4 feet of the vein-matter bear $91 19 silver pèr ton.

Sampled cupriferons ores yielded in silver as follows:

A. A gray copper ore, containing antimonial ores, a refractory ore for smelting, which forms the greater portion of the ore of the St. Lucas mine, contained per ton $93 60 in silver.

B. A highly oxidized ore, containing silver-copper glance, forming au average of 1 foot in width of ore, 30 feet below the surface, in the San Ignacio mine, contained per ton $161 78 in silver.

C. A still higher oxidized ore, mostly antimonial, with stains of leadochre, some malachite, and azurite, forming a seam 6 inches wide in the San Ignacio mine, close to the surface, yielded $259 05 in silver and $40 51

in gold; total, $329 56 per ton. This is the only sample from the entire district which has come under my notice showing an available quantity of gold.

D. A sample of azurite, apparently not carrying silver, from the outcrop of the St. Louis mine, yielded $106 81 in silver.

In order to acquire a good insight into the value of the ores of the district as a whole, from twenty-seven to thirty mines were visited, and the ores sampled as they occur, regardless of assorting. An average sample taken from all the samples thus obtained assayed $68 52 per ton silver as an average for the entire district. By proper assorting this yield can be raised to $143 91 per ton, as will appear below. The following is a list of the assays made, giving notes on the veins. from which the samples were taken.

I. Galena ores of Cerro Gordo:

1. Sampled 8 feet ore-width; much vein-matter; about ore to waste; from Freiburgh No. 1 mine; assay, $25 12.

2. Sampled 3 feet ore-width; about waste; easily assorted; some copper; from San Felipe mine; assay, $12 56.

3. Sampled 2 feet ore-width; about ore, waste; containing no copper or antimony; from Union mine; assay, $25 62.

4. 6 feet ore-width; about 4 ore, waste; some copper; no antimony; from San Aberlino mine; assay, $54 97.

5. 2 feet ore-width, in a vein 15 feet wide; about

ore to waste; contains some antimony and very little copper; from Union mine; assay, $91 10.

6. 4 feet ore-width; very ferruginous; hard to assort; traces of copper; from Front mine; assay, $58 11.

7. 14 feet ore-width; ore to waste; galena in spots; no copper; hard to assort; Guaymas mine; assay, $36 23.

S. 16 feet ore-width; very ferruginous; can be easily assorted; waste; from Union mine; assay, $45 55.


9. 17 feet ore-width; ore in seams; ore, waste; can be easily assorted; the only thing accompanying the galena are very soft oxides of iron, cemented together by an argillaceous mass; from San Felipe mine; assay, $12 56.

10. 6 feet ore-width; no antimony or copper; about ore, waste; the ore occurring in pockets; from Freiburgh mine; assay, $43 98. 11. 4 feet ore-width, in a vein 12 feet wide; ore, waste; not so

easily assorted; from Asteroid mine; assay, $42 46.

12. 14 feet ore-width; an average throughout all the stopes of the Union, Front, and Freiburgh mines; waste, ore; assorted by hand, but not very carefully; assay, $100 53.

13. 13 foot ore-width; Queen City mine; the vein is throughout 7 feet wide; can be assorted in extracting the ores from the mine easily toore to waste; assay, $84 82.

II. Copper ores of Cerro Gordo:

1. 8 feet ore-width, on outcrop; only stains of malachite visible; mine. not developed; cannot be called ore; sampled as a prospect; from Abundancia; assay, $6 28.

2.2 feet ore-width in vein 24 feet wide; mostly malachite and antimonial ores; easily assorted to ore, waste; from Abundancia mine; assay, $80 10.

3.2 feet ore-width; highly oxidized ore; mostly copper and antimonial ores; waste, ore; vein 10 feet wide; San Iguacio mine; as say, $316 14.



4. 7 feet ore-width; some galena; not refractory ore; ore, waste; from San Ignacio mine; assay, $161 78.

5. 8 feet width of the entire vein of No. 4; San Ignacio; can easily be assorted to ore waste; from poor portion of the mine; assay, $31 42.

6. 5 feet width of vein; sampled as it would be taken out before any assorting could be done; ore in spots; no galena; can be assorted easily by hand, say ore, 1 waste; from Grand Poder mine; assay,

$10 98.

7. 4 feet vein-width; docile ore; little lead, say ore waste; from the Guaymas mine; assay, $47 13.

8. 23 feet ore width, being two separate pay streaks in a vein 6 feet wide; does not require much assorting; contains some antimonial ores; from Candelaria mine; assay, $105 39.

9. 3 feet ore-width, vein 4 feet wide; contains considerable galena, is assorted to about ore 3 waste; contains antimonial ores; from San Lucas mine; assay, $108 06.

10. A vein 3 feet wide; San Benito mine; about ore waste; no galena. This is a sample from the mine and from the dump which was assorted ore waste; ore can be amalgamated, and may be called an average; assay, $106 83.

11. A vein which is 27 feet wide at the outerop, showing about 10 per cent. of galena and silver copper-glance, very sparingly distributed throughout the vein. One ore-seam is 18 inches, widening and narrowing along the outcrop; from Abundancia; not developed much; assay, $7 85.

12. 33 feet ore-width; mostly oxidized ores; vein is 5 feet wide easily assorted, to about ore, waste; from Asteroid mine; assay $105 75.

13. Several ore-seams, from 2 inches to 1 foot in width, on a vein 6 feet wide, making in all probably about 26 inches of ore width; from Fermin mine; ore fit for wet process of beneficiation; assay, $115 15.

14. The ores from the Robinson, Chevall, Sacramento, Reindeer, Omega, San Benito, Tresilos, Alpha, San Louis, and Queen of the West, were also sampled. But little work has been done on these mines. They are situated in the southern portion of the district. An average assay of $42 11 per ton was obtained. The ores of all these resemble one another very much, and none of the veins exceed 63 feet in width. All the foregoing samples, taken together, give an average of $68 52 silver per ton. They were taken with the object to get at the real merits of the mines as a body, with little assorting. They can certainly all be assorted to ore to waste, with a loss of 25 per cent. of their actual assay value. This would bring the average to $154 17 per ton; and even if we admit a loss of 30 per cent., the silver value would still be $143 91. Much of the success of the district depends upon the careful classification and assorting of the Those ores bearing much gangue matter, and at the same time docile, (highly oxidized,) can easily be assorted from the others, and reserved for wet amalgamation, as, for instance, the ores from the Grand Poder, Candelaria, Valenciana, Tresilos, Mejicana, Portuguese, and San Benito mines. Those veins carrying refractory ores, by far the majority, must be freed from the accompanying gangue matter as closely as possible and beneficiated by smelting. This dressing is rendered easy by the great differénce in the specific gravity of the ore and the barren rock. The most prominent mines are, the Union, San Ignacio, Freiburgh. San Felipe, St. Lucas, and Belmont; about sixty mines are located an prospected. I have pointed out already that the mines can be divided


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