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of this winze, on the 360-foot level, the recently reported strike of $300 ore was made.
Descending No. 3 shaft to the depth of 340 feet, a small cross-cut made from the shaft on the hanging-wall side in the vein, which at this point seems to dip flatter into the hill, exposes 1 foot of fine ore. A sample from it assayed at $643.28 per ton. This same body of ore again makes its appearance in the shaft at the 360-foot level with an average size of 6 inches, assaying $411.34 per ton. The total size of the ledge in the shaft at this station is 18 inches.
From the main shaft along the 360-foot level, west to winze, the vein is small and bunchy but rich, and the stopes will doubtless open well.* The Extension shaft on the west end, No. 3 shaft on the east end, together with winze from 280-foot to 360-foot levels, and the 360-foot level itself, as far as opened, permit an estimate to be made of the number of tons of ore above this level, between the aforesaid points. Total amount of ore in sight, 2,514 tons. Average size of vein, 14 feet. Average value of ore per ton, $178.98. These last figures ($178.98) are taken from the average assay value of the ore in the bottom of the 280-foot level. The recent discovery of richer ore on the lower level will probably increase the value of the ore in the stopes above the 360-foot level.
The main shaft has been sunk 40 feet below the 360-foot level, but is not in the vein. The vein from the 360-foot level appears to change its dip, and, to preserve a uniform incline in the shaft, it has been sunk regardless of the vein, at least for the present. Returning to the 63-foot level, 404 feet east of the bifurcation, following the North Fork, is the Old Black shaft. The stopes overhead of this level through to the New Black shaft have been exhausted. West of the Old Black shaft, above the 63foot level, for a distance of 100 feet, the stopes are worked out. A cross-cut in the 63-foot level, 100 feet west of shaft, through to Boyd shaft, Las exposed an 18-inch vein of rich ore on the south side of the drift, assaying $200 per ton. The distance through this cross-cut to the hanging-wall vein is 109 feet 6 inches.
Between the Old Black and Summit shafts the ore above the 63-foot level is nearly all stoped out. In the bottom of the 63-foot level, between the New Black and Summit shafts there is a fine body of first-class ore, extending, it is supposed, down to the 120-foot level. Its size is unknown, as the 120-foot level is not as yet under it; the body itself is dipping rapidly west. At present, this stope is furnishing daily 10 tons of first-class ore. The mine assay of these stopes, October 26, was $339.12.
The ore from the Black shaft stopes contains a large quantity of manganese, and has always been very rich. Selected ore, worked from the old stopes, has reached the value of $720 per ton. The driving forward of the lower levels will develop all this ground, which, up to date, is unprospected in depth.
Ascendivg 32 feet through the chute at the end of the cross-cut, (100' 9'' west of Black shaft,) on the hanging-wall vein, the ground acquired by the compromise between the Meadow Valley Company and the Washington and Creole Company is reached.
This ground, forinerly in the possession of jumpers, was badly gutted at the eastern end, but fortunately their shaft on the west ground, now owned by the Meadow Valley Company, did not strike the vein.
Although considerable ore has been extracted fro this claim, there still remain, between the 63-foot level and the surface, 432 tons, of an average value of $152.30 per ton. In depth the prospects are favorable.
The Summit shaft has been sunk 400 feet, (vertical.) It was sunk on the vein, and, ex: cepting the first 30 feet, has always been in poor ore. For the last six months no work has been done in it. It is timbered and has two compartments. The present indications of the vein in the bottom of the shaft are poor. Nineteen and one-half feet east of the Summit shaft, on the 120-foot level, there is a cross-cut from the foot to the hangingwall vein. Two hundred and fourteen feet south of this level the vein under the Creole ground was struck by the cross-cut and found to be very poor. Returning to a point in the cross-cut, 28 feet 9 inches north of the vein, and running through the quartzite 105 feet, the vein under the Boyd stopes has been again found. Although not as yet developed to any extent, the mine assays of October 26 showed the bunches of ore to be worth $109.90, $144.44, and $113.04 per ton. West of the Summit shaft, (footwall vein,) the 120-foot level has been driven 150 feet. A raise is now being made to .connect this level with the stopes already described in the bottom of the 63-foot level.
Four hundred and sixty feet northeast of the Summit shaft, along the 120-foot level, (foot-vall vein,) is the Receiver's shaft. This shaft was sunk perpendicularly 31 feet to this level. The immediate cause for sinking it was to prevent jumpers from claim. ing the ground. Simultaneously with its sinking, jumpers sank a shaft on the Pioche vein.
Since writing the above this level has been pushed forward 114 feet west of the shaft, the rein meas. uring 30 inches, and assaying $329 per ton.
+ Samples are taken every two days from all the stopes and drifts in the mine.
From the 120-foot level the Receiver's shaft was sunk on the vein to a total depth of 200 feet, and at the same time the ledge was traced through on the 120-foot level to the Summit shaft west, and to the Challenge shaft east, in order to prove the vein. Between the Summit and Receiver's shafts the vein is distinctly traced, and, although somewhat irregular at the latter, further west it is a bold, hard ledge, varying in size from 1 foot to 34 feet, assaying from $25 to $82 per ton. None of this
ground has been at all prospected, and, no doubt, in depth, good ore will be found. The 200-foot level of No. 7 shaft connects with the Receiver's shaft.
Between the Receiver's and Challenge shafts, on the 120-foot level, very rich ore has been extracted. In the Receiver's shaft there are several places which indicate good ore, but no drifts have ever been run to explore the ground to the west of it, into which, probably, the ore-chutes from the Challenge ground have passed. Forty-five feet east of the Challenge shaft the 120-foot level connects with a shaft, which in turn connects through a drift with No. 7 shaft. In order to decrease the expense of hoisting the ore, and to facilitate its transportation, a tunnel was driven north from Receiver's shatt, 227 feet through the country-rock, corresponding with the 120-foot level. This is called the Tunnel east of 120-foot level.
As soon as the raise from the cross-cut on the 120-foot level to the Boyd stopes is open, all the ore from that portion of the mine, which is now conveyed west, will come out through this tunnel. At present everything east from the Black shaft passes through it, and is dumped with the ore from No. 7 shaft* into the ore-house situated on Meadow Valley street, in front of the Meadow Valley Company's office,
No. 7 shaftt is an inclined shaft sunk on the vein to a vertioal depth of 500 feet. Average dip 51°. The shaft has two compartments,
A steam-engine, (similar to the one at No. 3 shaft,) situated at the mouth of the shaft, does the hoisting for this portion of the inine, The first drift opened from this shaft was at 97 feet below the surface. East seventeen feet on the same level the ledge first made its appearance. All the rich ore on this level east for 140 feet, and west to Receiver's shaft, has been stoped out. The length of the rich stope on this level east was 79 feet, and west 78 feet.* Tho ore remaining above it assays as follows: East of shaft, $32.97 ; west of shaft, $35.12 per ton. Size of the vein: east one foot, West two feet. The ore on the west side runs as low as $12.56 to $10.99 per ton. From the first to the second level the distance is 77 feet 2 inches; dip 48° 30'. West from the shaft on the 200-foot level, for 45 feet, the stopes are worked out. A small pillar of low-grade ore, 58 feet long, follows the stope, and then for a distance of 24 feet it is worked ont to the level above. Under foot, at the end of this stope, there is a chute to the level below,
East from the end of the last-mentioned stope, for 50 feet, the ground is solid overhead ; then follows a stope 35 feet long and 20 feet high.
Twenty feet farther west the drift terminates in quartzite. Value of ore remaining in stopes, from $9.42 to $15.70 per ton. For 44 feet under foot, on the east side of shaft, (200-foot level,) it is solid; overhead for 100 feet it is stoped out; immediately adjoining is a barren streak 44 feet long,
The first chute of fine ore succeeds this barren spot, and is opened for 13 feet, then unworked for 39 feet, and the ore again exposed for 43 feet. Average size of the
vein, 2 feet. Average value of the ore $193.82 per ton. Between the 200-foot and 100-foot levels 815 tons of ore may be estimated as in sight.
The ore-chute mentioned east of the shaft, on the 100-foot level, crossed the shaft at the 200-foot level. From the 200 to the 280-foot level, it is 74 feet; dip, 58° 30'. The drift west has been driven 76, feet; the vein is poor, and averages two feet. The orechate is 50 feet long; average value, $7.80 per ton.
in the east drift on this level, 66 feet from the shaft, there is a chute from the level above. Fifty-five feet from here there is a winze being sunk, and overhead there is a stope.
One hundred and thirty-seven feet in the drift beyond the first stope there is a break in the vein. At 160 feet a second stope has been commenced, but is raised only a short distance. Adjoining this stope a fine ledge makes its appearance, extending 26 feet; the ledge is hard and rich. For 63 feet beyond the raise the ledge is left on the footwall, and appears pinched until it reaches the third stope, which is opposite the cut made by the Pioche Company. This stope has been opened for 24 feet, and shows a fine vein 3 feet in size. The amount of ore exposed by the stopes on 280foot level is 454 tons;; value per ton, $153.44; average size of vein, 24 feet. It is to the east of this same stope, above and below it, ihat the Pioche Company overraų the Meadow Valley Company's line, and extracted 150 tons of ore, valued at $250 per ton.
To the east of the Meadow Valley Company's line, in the Pioche Company's ground, * That is, ore extracted from the eastern end of the mine. 1 The position is indicated on the chart.
Although this oro is not opened by the 100-foot level, there can be little doubt of its being found Then the.lerel is pushed forward and the stopes raised.
a winze has been sunk 100 feet lower than this level, and excellent ore has been found pitching from their winze into the Meadow Valley mine.
This is a most favorable prospect for future developments in the lower levels, east from No. 7 shaft. From the 200-foot level to the 440-foot level, No. 7 shaft descends 210 feet, on an angle of 52° 15'. The 360-foot level has not as yet been started. The 440-foot level, on the east side of the shaft, is in 40 feet. As yet no rich ore has made its appearance, nor is it expected for the first 150 feet or more.
The ledge in the drift now assays $9.42 per ton. The shaft is 30 feet below this level; + the vein appears to be dipping flat into the hill, and is not in the bottom of the shaft.
General observations.-On acocunt of the narrowness and peculiar character of the vein, and other considerations, shafts Nos. 1, 3, and 7 should be kept 200 feet ahead of the work. Levels should be regularly opened and driven. I would particularly recommend that the 360-foot level be connected throughout the entire mine. The probabilities are that this level will open up valuable unprospected ground between shafts Nos. 3 and 7, and afford greater facilities for working the various ore-chimneys from the east, all of which are pitching west, and in depth will be found far beyond the plane of their original boundaries. The only profitable manner of extracting the ore in this mine is by overhead-stoping. The character of the ore and the formation of the encompassing walls render underhand-stoping unprofitable.
The store-house at mine is well supplied. The present stock on hand amounts to $12,933.28. (Vide mine store-house report, November 1, 1871.)
It is absolutely necessary for the company to keep a largo supply of hardware and materials on hand, as there are no firms in Pioche, with sufficiently assorted stocks, with which the company can deal. The recent fire showed the importance of the company having its own store-house well supplied.
The mill.-Everything at the mill is in good condition. The scarcity of water has prevented the use of the concentrators. By the middle of November the new engine will be in position. The additional two pans, en route, when in place, will increase the productive capacity of the mill about 180 tons per month.I
The Horn pans I did not examine, but am informed by Mr. Forman that they are in excellent order, and, so far, no amount of wear by action of the chemicals, exceptiog on two of the pans, is at all observable. In future, the bottoms of the shells should be cast thicker than those now in use.
The store-house at the mill contains a large stock of chemicals, quicksilver, castings, &c. (Pide store-house report, November 1, 1871.) Value of present stock on hand, $46,678.08; supplies en route, about $25,000.
The assay office at the mill should be immediately removed from its present position. Its proximity to the mill endangers the latter. For the sum of $1,800 a brick office with a tin roof can be built. One mile below the mill, in Dry Valley, the company owns an interest in a large spring which is said to run 200 inches of water. The water, by analysis, proves to be the purest found in the neighborhood. The office at the mine is 962/ feet higher than the spring, and distant from it ten miles. I would call the special attention of the board of trustees to the possibility of bringing this water to the mine and erecting the mill in Pioche City. At a cost of $85,000, 10 inches of water can be brought into town from this spring.
The ore-hauling account for the coming year will, in all probability, exceed $100,000.
In case the company should deem it advisable to bring the water into town, (the cost of which can only be determined after a thorough examination of the country,) the old mill could be converted into a tailings-mill. There are on hand at the mill, in the reservoirs, 14,000 tons of tailings, averaging $33.75 per ton,ll and 2,000 tons of slum, averaging $106.76 per ton.
Location of mine, Pioche City, Lincoln County, Nevada.
The gangue is quartz, decomposed. The silver occurs as a chloride, combined likewise with carbonates and sulphurets of lead. (Vide report.)
Size of vein, from 1 inch to 9 feet.
* The drift is in 114 feet, assaying $56 per ton. (November 14, 1871.)
NOTE.-If the present (monthly average) high grade of the ore is reduced to a lower standard, say $120 per ton, the mine will be worked to a greater advantage, and it will prove in the end more profita ble to the stockholders.
Since arrived, and now running. (November 22, 1871.) & Measured by civil engineers.
Average value of tailings, estimated from monthly mill reports from 15th Jaly, 1870, up to date, (October 31, 1871,) shows $33.86 per ton.
Average size is from 2 to 24 feet, irregular.
No. 3 shaft, 400 feet deep, vertical measurement; No. 7,500 feet deep, vertical measurement; lowest level at east end of mine, 440 feet; lowest level at west end of mine, 360 feet.
Ore in sight in mine.
Tons. Gross value. Above 63-foot level.....
219 $27,032 04 63-foot level to 120-foot level..
893 123, 444 76 120-foot level to 200-foot level.
752 120, 470 40 200-foot level to 280-foot level.
2,275 385,726 25 280-foot level to 360-foot level..
449, 955 72 Boyd stopes...
432 65, 793 60 East end, No. 7 shaft. 100-foot level to 200-foot level......
815 157,963 90 200-foot level to 280-foot level.
454 69, 661 76 Ore at mill, November 1, 1871, (value, $140 per ton)...
1,500 210, 000 00 Totals ..
9,854 1, 610,047 83
In reservoirs, November 1, 1871.
$472, 500 00 213, 520 00
Total cost of mining, milling, taxes, &c., estimated from accounts of 1870 and 1871, $44.11 per ton.
Average bullion yield for same period, $105.34 per ton, or 73.4 per cent. of gross value of ore worked. Average bullion yield for August, September, and October, 1871, $114.78 per ton.
The following is the very complete biennial report of the superin. tendent and secretary of the company for the fiscal year ending July 31, 1871:
PIOCHE, NEVADA, August 5, 1871. To the president and trustees of the Meadow Valley Mining Company:
GENTLEMEN : Herewith I hand you statement of operations at the company's mine and mill for the fiscal year ending July 31, 1871.
During the company year just ended there have been extracted from the mine 16,500 tons of ore obtained from the following sections :
Tunnel west of 63-foot level
Tons. 7,793 3,5111 1,3491
374 2231 2,335
You will observe from the above statement that tunnel west has been the most productive section, having produced nearly one-half of all the ore extracted during the year; but the ore above that level (the 63-foot level) is now nearly exhausted, and hereafter the principal supply must be boisted through shafts Nos. 3 and 7.
The development of the mine has been greatly retarded by our inability to do the necessary amount of hoisting with the whims, which have been taxed nearly to their utmost capacity hoisting ore to keep the mill supplied, and consequently but comparatively little sinking and drifting could be done below the tunnel-levels.
During the month of July steam hoisting-works were erected upon shafts Nos. 3 and 7, and are now in successful operation, obviating that difficulty, and we are now able to proceed rapidly with the sinking of shafts, drifting, &c.
No. 7 shaft bas attained a depth of 364 feet. The average dip of the vein in this shaft is 53° to the south.
The east drift 200-foot level in this shaft is being driven on the ledge, and in very fine ore. Average samples taken from the face of the drift for the past week show an average assay of $216.66 per ton.
At 280-foot level east drift is being driven forward as rapidly as possible to cut the ore-chute that we have left under the track-floor in 200-foot level.
Station at 360-foot level is now being opened.
Sumwit shaft has been sunk to a depth of 369 feet, and, being upon a portion of the mine that has been comparatively barren from the surface, we bave stopped work upon it for the present. The average dip of the vein in this shaft is 58° to the south.
No. 3 shaft has been sunk to a depth of 285 feet, and the work of sinking is being vigorously prosecuted. The average dip of the vein in this shaft is 77° to the south.
The 280-foot level, wbich is just being opened, promises well for a large amount of first-class ore. The west drift from this shaft is being driven in the ledge, and in very fine ore. Average samples taken from the face of the drift for the last ten days give an average assay of $205.67 per ton.
Winze No. 2, 160 feet west of No. 3 shaft, is being sunk from the 200-foot level to connect with the 280-foot level, and is now down 13 feet, showing first-class ore.
From present indications the section lying between Discovery shaft and No. 3 shaft, and extending from 200-foot level to the 280-loot level, will produce a very large amount of first-class ore.
The ledge throughout the mine below the 200-foot lerel contains much more picking, ground than it does above that level, and I anticipate a large reduction in the cost of extraction.
From careful measurements made, I estimate the amount of ore developed, that will mill $80 or more per ton, to be 6,758 tons, and in the following sections of the mine:
Tons No. 7 shaft, above 280-foot level
1, 476 Tunnel west, above 63-foot level Washington section .
701 No.3, below tunuel-level..
3,767 Black shaft ....
In this estimate I have not included the body of ore lying between No. 3 and Discovery shafts and the 200 and 280-foot levels, nor any body of ore that is not fully developed and its full extent known.
But little work has been done during the year upon the outside mines owned by the company, except the necessary amount required to comply with the mining laws of the district.
In several of these mines the indications are quite as promising as they were at the same depth in No. 7, and I would recommend the sinking of shafts upon them to the depth of 100 feet or more to develop them.
During the past three months the company's mill at Lyonsville, Dry Valley, has been thoroughly overhauled and repaired, the old pans having been replaced by new ones of the most approved pattern, and three new boilers have been added, making the mill complete in all of its appointments, and in much better condition for doing good service than when it was first built.
During the first few months the will was run much time was lost for want of an adequate supply of water. The ditch for supplying the mill was dug across a saudfat, and the water was absorbed and evaporated during the summer, and the ditch frozen up during a portion of the winter.
This has been remedied by building a flume to take the place of the ditch, and corering it with earth to a sufficient depth to prevent freezing during the winter.
During the year just ended 17,458 tons of ore have been received, and 16,172 tous reduced by the mill.
The necessary reservoirs have been constructed for catching tailings, and no tailings are now allowed to run to waste.