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have generally done vastly better than the companies who preceded them, working the same veins.
On the Kansas lode, for instance, in Nevada district, there were, in the latter part of the year, nine claims worked, the majority of which turned out exceedingly well, so that the lode produced at that time much more gold than ever before. Wheeler & Sullivan, who work the “ First National" claim on this lode, were furnishing 40 stamps of the New York Mill with ore. Richards & Co. were deepening their shaft on the Ophir Company's claim, and were in good ore all the way. The Garrison claim was worked by Wolcott & Co., who were both drifting and stoping, and took out good pay ore. Ira Easterbrooks, who took the lease of the Mead claim off the hands of William Lyon & Co., was drifting and stoping in his mine, which presented a better appearance than ever before. D. L. South worth was sinking on Waterman's claim, the next one east. Mr. Root was obtaining rich ore from his claim on the Kansas, near Boston Mill. On the second claim east of Root's, Andrews & Sullivan were raising large quantities of five-looking ore, which was being crushed at Lake's Mill, on North Clear Creek.
The English Kansas Gold Mining Company were doing well on their claims purchased some months ago of J. F. Hardesty.
Another claim, between Roots and that of Andrews & Co., was being worked in a small way, and the ore hoisted by a windlass.
The second-class ores from this vein assayed, at the time spoken of, about 1.4 ounces of gold per ton, and the yield in the mills was given to me as 4.1 to 5 ounces per cord. First-class ores brought, at Hill's works, about $100 per ton.
The Kent County lode, about 400 feet above the foregoing, was also very actively worked during last year. Mr. Eilers visited, in the fall, the Ætna Company's ground, 1,000 feet in length, which was leased by Messrs. Nichols, Roe, Fisher, and Mitchel. These men started to work the mine with almost nothing, but were doing exceedingly well at the time of this visit. The mine was 320 feet deep, and the force employed in three levels and on the surface was twenty-seven men. The principal stoping was done between the first and second levels, 100 and 160 feet from the surface, both east and west from the hoisting-shaft. Here a great mass of very rich ore had been found sticking to the hangingwall, which had been overlooked in the old stopes on account of a thin sheet of slate which separated it from the ore on the foot-wall. About 30 tons of ore were hoisted per day, a considerable portion of which was first class, bringing at the smelting works from $95 to $126 per ton. The second-class ore averaged about 7 ounces per cord. This claim is very well opened. The levels are all connected by winzes, and sinking for reserves was steadily kept up. In the rich ground spoken of, the vein was over 5 feet wide, containing the usual mixture of iron and copper pyrites, blende, and quartz.
This claim connects by drifts with a neighboring one leased by the Bradley Brothers, so that in both of them the ventilation is very good. The latter claim is 450 feet long, and is opened to a depth of 200 feet, but at the time of Mr. Eilers's visit it was idle, on account of litigation with the owners of the Ralston Company lode, which appears to be a feeder to the Kansas. There were a large number of claims worked on the lode which could not be visited.
The Prize is situated opposite the foregoing. It strikes northeast and south west, and dips steeply to the southeast, like the two last named. It is opened for a length of 900 feet, in two claims of respectively 400 and 500 feet. The latter belongs to the Cornwallis Company. Neither of these claims has been opened long, but the capacity of each, last fall, was 25 tons per day. First-class ore contained $94 in gold and silver, about 8 ounces of which was silver. Second-class ore assayed 6 to 10 ounces of gold per cord. The Iron Ram is situated in the same neighborhood, and can deliver about 10 tons per day. The best ore assays from $50 to $80 per ton. On the California, situated on the same hill-side with the Kent County, the deepest shaft was down 740 feet, in the fall. Another one was 360 feet deep; and there were several others of less depth. The vein is from 2 to 3 feet wide, and dips and strikes very nearly parallel to the Kent County and Kansas. First-class ore from it is reported to contain $150 per ton in gold and silver. For such ore Professor Hill pays $75; and I am informed that one claim on this vein (Harper's) can furnish 12 tons of it per week. Stalker's claim is reported to furnish nearly as much. If this is really so, these claims contain exceptionally rich ore. (See my last report.) The first-class ore of this vein contains about 4 per cent. of copper, and the second-class 11 per cent. For second-class ore, which is said to assay, on an average, 2 ounces of gold and 10 to 15 ounces of silver per ton, Professor Hill pays $37 per ton.
Of lodes in other districts, the Illinois Central, Burroughs, American Flag, and Gunnell, (the latter since the middle of summer, have been actively worked, and produced much ore. The Gregory, Parmelee, Briggs, Bates, Bobtail, and Fisk were all idle in the fall and full of water. The Fisk and Bobtail will be the first lodes drained by the Bobtail tunnel, driven by Mr. Rogers and others. This tunnel was in 300 feet in the fall, and 150 feet further were expected to bring it to the Fisk, which it will strike at a depth of about 450 feet below the outcrop.
The principal mines in the vicinity of Central City have been described very fully in my last report, and, as no very important changes have taken place, it is unnecessary to go again over the same ground.
The following statistics of the average contents of ores in gold and silver, from different districts in the vicinity of Central City, hare been kindly furnished me by Mr. A. von Schulz, whose facilities as assayer in Central City enabled him to take his averages from a large number of samples assayed within the last year:
Per ton, in coin. •Gregory district: Milling ore, average of 72 samples.. Smelting ore, average of 35 samples
169 Nevada district : Milling ore, average of 56 samples.
35 Smelting ore, average of 32 samples
Russel gulch :
37 Smelting ore, average of 23 samples
Central City district :
35 • Eureka district : Milling ore, average of 17 samples.....
41 Lake district, (two miles southeast of Central City:) Milling ore, average of 12 samples...
24 From notes submitted to me by Colonel G. W. Baker, of Central City, I reproduce here the following statistics, showing the relative values of gold and silver in Colorado pyritous gold ores. According to 77 assays, made by the territorial assayer at Central City during the last two years, and certified by him, the average contents of these samples, which represent a great number of veins from different districts in the vicinity of Central City, in gold and silver, are: gold, $61.93; silver, $37.30. The average of silver is here, however, larger than usual' in the pyritous gold ores of Colorado, because some of the ores assayed are more properly silver than gold ores. In the following 28 of the above assays the usual proportion of gold and silver present in the gold-ores is more accurately given:
Taking 237 assays of second class and 102 of first-class ore which were made in the territorial assay-office somewhat over a year ago, and averaging those made from ores of particular districts, the contents of gold and silver vary for the different districts as follows:
In the assays made by Mr. A. von Schulz about the same time, the proportion of gold and silver contained in the ores of the various districts, and obtained in the same manner as above, appears as follows:
Milling ores, (second class.)
Mr. Burlingame, the territorial assayer, and Mr. A. von Schulz both certify that the above assays from their books were made from ores from the following number of different lodes in the districts named: From Gregory district, from 46 different lodes; from Nerada district, from 51 different lodes; from Illinois Central district, from 17 different lodes; from Russel district, from 64 different lodes; from Central City district, from 34 different lodes; from Enterprise district, from 36 different lodes; from Eureka district, from 14 different lodes; from Lake district, from 20 different lodes.
It is seen that the proportion of gold and silver in the ores varies considerably in the averages from the two assay-offices; but they seem to establish the fact that there is really more silver in the Colorado goldores than was assumed in Mr. Reichenecker's article in my last report. Taking the average of 428 assays made in the territorial assay-office and in that of Mr. A. von Schulz, at Central City, we find the proportion of gold to silver in Colorado gold-ores: gold, $22.56; silver, $17.51 per ton of ore.
Accepting the last statement, which is taken from the greatest nonber of assays, as the one which probably comes nearest to an average, there would be to $100 gold in the ore $77.62 silver. The gold bullion
of Colorado contains, however, according to Colonel Baker, only $20 silver to every $100 in gold.
The great loss of gold, silver and copper in the Colorado stamp-mill process I have discussed in my last report. It is there shown that the actual saving is only about 40 per cent. of the assay value of the ore. From the above it appears that the loss of silver, considered for itself, is much greater, as, of $77.62 silver, only $20 are actually saved; the loss is, therefore, $57.62 in silver to every $100 in gold saved, or 74.2 per cent. of the original contents of silver in the ore.
The above assays, being of small samples only, may not represent the true proportion of gold and silver, but the figures obtained from them must evidently not be very far from the truth. In this case it is evident that concentration and smelting of the ores would be far preferable to the present mode of working these ores, even if we accept, in this case, the maximum loss of brittle silver-ores in concentration, i. e., from 20 to 30 per cent. In this connection a process of beneficiating ores containing both gold and silver, and little galena, by means of smelting, as practiced in South Austria, is worthy of the higest consideration, and I draw attention to it for the benefit of those most directly interested. Though practiced under conditions somewhat dissimilar from those in Colorado, it seems to me that it would fulfill, in that country, the requirements of the times. The process was witnessed and described by Mr. John A. Church, E. M., who kindly permits the use of his article. It will be found in full in a subsequent chapter of this report.
Professor Hill's smelting-works at Black Hawk have been enlarged during the summer by one smelting-furnace, a reverberatory of the same pattern as the two older ones. This, in itself, is proof that the mines in the vicinity of Central City furnish much more ore than before, for it is well known that the manager of these works is very cautious, and not apt to invest additional capital unless he is certain of a steady supply of ore. Nevertheless, the old and, I am sure, unreasonable dissatisfaction among miners, who have for years joined in the cry for more bene. ficiating works and higher prices for the ore, has not been allayed, so that Professor Hill has been finally obliged to defend publicly his policy and his works. I reprint his letter here, because it contains many valuable statements; it was addressed to the Central City Register:
Articles frequently appear in the papers of Central City, similar to yours of a few days ago, under the head of “ California mining.” Such articles, so far as they exert any influence, are calculated to convey false impressions. Besides, there are persons who, either from ignorance or designedly, are constantly making false statements about the comparative
cost of treating ore in this and in other places. It is stated in the article referred to that, in California, stamp-mill rock, worth $8 per ton, and sulphurets, worth $15 per ton, can be treated with profit. How are they treated! The stamp-mills in this county treat ores for $3 to $5 per ton. If it is claimed that the milis here do not save so large a proportion of the gold as they save in California, it must be remembered that saving gold, when it is in combination with almost every base metal and sulphuret that is known, is a very different thing from saving gold when it exists free in a quartz matrix. The writer also says that in this county gold silver ores worth from $60 to $75 per ton, and rich in copper, are not available at the present time, and thinks it is a shame that such ores cannot be worked here with profit.
Ores containing gold and silver to the value of $60 per ton, in currency, and allowing (as the writer says they are rich in copper) that they contain 8 per cent. of copper, are worth here $36 per ton, without any cost beyond that of delivery at the smeltingworks. If ores worth $8 to $15 per ton in California can be mined and reduced with profit, and if in Colorado ores worth $36 per ton, over and above all costs of reduction, cannot be treated with profit, it would seem that the great difference between California and Colorado was in the expense of mining and not in the expense of reduction.
It would be instructive for those who complain of low prices of ore in Colorado to inquire what prices are paid in other places.