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The yield of the quartz varies generally from $14 to $17 per ton, and the cause of the falling off in the gross product during 1863-'84 was the great scarcity of water, which necessitated the erection of a flume at an expense of $40,000.
The principal expenses attending the working of auriferous quartz are the cost of extracting the quartz from the mine and its subsequent treatment in the mill. With regard to the first no general data can be given, for the amount paid for mining varies from $1 50 to $26 per ton. It is dependent upon the hardness of the quartz; the hardness of the country rock in which the vein is encased ; the relation which the auriferous portion of the vein bears to that which is barren; the depth of the workings, and finally the amount of water in the mine, and whether it has been drained by adits or pumping. As a general rule, however, it may be assumed that in the case of large veins, or those which exceed five or six feet in width, that the cost of extraction will be from $1 50 to $6, and that the total cost of mining and milling will not be more than $7 or $8 per ton under any circumstances.
With regard to the milling expense, however, we have accurate data to follow, and these are not much affected by change of locality.
The mills are generally situated in close proximity to the mines, for the difference between the cost of running a steam and a water mill is almost always less than the cost of hauling the quartz for any distance by teams. The mills are of nearly ail sizes and capacity, and vary from those which have only two or three stamps to those which have forty-eight. The weight of these stamps is from 400 lbs. to 1.000 lbs., and they are run at a velocity varying from 50 blows to 80 blows per minute and fall from 10 to 14 inches. The favorite weight would appear to be about 650 lbs., with a fall of 12 inches and a velocity of from 60 to 70 blows per minute. It is generally assumed that a ten-stamp mill, with stamp of 550 lbs., falling 12 inches and striking 60 blows a minute, will crush 124 tons of ordinary quartz in the twenty-four hours.
The mills which are moved by water power alone are situated either on the banks of rivers and streams where the water is free, or else the water is conveyed to them by a flume from some neighboring ditch and sold at a price which is generally the result of special agreement.
In the case of steam mills the fuel is always a principal item of expense: Wood—either pine or oak—is universally employed, and costs from $2 to $1 50 and even $5 per cord. Oak, when the two can be obtained and are equally convenient of access, generally costs one-third more than pine and is regarded as being nearly twice as valuable for steam purposes. The mean amount of fuel consumed in the steam quartz mills of California is not far from 0.164 cord for each ton stamped. The prices paid for labor in the mining towns is still very high, and in many cases operates as an effectual barrier to the working of some quartz mines. First class miners receive from $3 to $3 50, and in some cases as high as $3 75 per day, while ordinary laborers receive from $2 to $2 50. In the milling of quartz the item of labor is generally from 60 per cent. to 75 per cent. of the total expense. In mining the proportion which this item bears to the whole cost is much greater, so that it is easy to perceive to what an ex
tent a reduction of wages would operate in favor of the quartz mining interest of this coast.
The mercury that is used in the process of amalgamating is derived entirely from the Californiá mines, and generally costs the miner about sixty-five cents per pound; very little, however, is lost in the mills when proper care is observed, and this item of expense is insignificant, for it rarely exceeds six ounces for each ton of quartz treated, and' frequently falls below this amount. The average cost of milling quartz in the various mills of California
be stated as follows: In water mills, when water is free..
$1 22 per ton of 2,000 pounds. In water mills, when water is purchased. 1 60 per ton of 2,000 pounds. In steam mills
2 14 per ton of 2,000 pounds. It is very difficult to state, even approximately, what is the present average yield of the quartz from the California mines. It is probable, however, that it has not varied much within the last five years, and in 1861, taking the returns from those mines which were at that time believed to be profitable concerns, it was at the rate of $18 50 per ton. The two extremes were a mine in Grass valley, which was yielding at the rate of $80 per ton, and another at Angels, in Calaveras county, where the quartz only paid $5, and was still being worked at a small profit. I remain, very respectfully, yours,
Mining Engineer. J. Ross BROWNE, Esq., Statistical Commissioner.
CONDITION OF GOLD AND SILVER MINING ON THE PACIFIC COAST.
1. Decrease of yield.-2. Export of treasure from California.-3. Receipts from northern
and southern mines.—4. Comparison of receipts and exports.5. Quartz yield increasing. -6. Uncertainty in quartz mining.-7. Professor Ashburner's statistics.—8. Rémond's statistics.-9. Pulverization of quartz.-10. Amalgamation of gold.-11. Sulphurets and concentration.-12. Chlorination.-13. Gold in loose state.--14. Placers.--15, Cement mining.–16. Hydraulic mining.-17. River mining.–18. The Haquard quartz mine.-19. Sierra Buttes mine.-20. The Allison mine.-201. The Eureka mine.--21. Smartsville Blue Gravel Company's mine.--22. Profits of mining generally.-23. Difficulties of getting good claims.--24. Comstock lode, the most productive in the world.-25. Comstock mining companies.—26. Quartz mills in Nevada.-27. The pan.-28. The Wheeler pan.—29. The Varney pan.-30. Knox's pan.—31. Hepburn pan.–32. The Wheeler & Randall pan.-33. Estimated yield of various mines.--34. Assessments levied.--35. The Gould & Curry mine.-36. The Ophir mine.-37. The Savage mine.—38. The Yellow Jacket mine.-39. The Crown Point mine.-40. The Hale & Norcross mine.41. The Imperial mine.-—42. The Empire mine.-43. Productive mines of Reese river. _44. Yield of various silver districts.-45. Improvements in silver mining.
1.-DECREASE OF YIELD.
The first fact in the condition of gold mining in California is that the yield is and for the last thirteen years has been decreasing. We know this by the concurrent testimony of the miner, by the decrease in the traffic of crude bullion, and by the decline of the exports of gold. No record is kept of the amounts taken from the mines, and our best evidence in regard to the produc
H. Ex. Doc. 294
tion is furnished by the reports of the receipts and shipments by express and steamer. From these we can get an approximation sufficiently near to serve all general purposes. The gold yield of California reached its culminating point in 1853, and the exportation of treasure, which rose in that year to $57,000,000, gradually fell until 1861, when it was $40,000,000. Then the silver of Nevada and the gold of Idaho began to come in and the amount of the shipments rose again.
2.-—THE EXPORTATION OF TREASURE FROM CALIFORNIA.
The following table shows the amount of treasure manifested for exportation from San Francisco :
It is well known, however, that this sum is far less than the total production of the coast. In the first place about $45,000,000 must be added for the amount of gold and silver now in use in the Pacific States and Territories for currency; that amount being the estimate made by experienced bankers.
A second allowance must be made for gold jewelry and silver plate made in the country, and for specimens of nuggets and rich ores, the value of which may be $5,000,000. Many of the miners in remote camps bury their gold dust until they are ready to return to the Atlantic coast, and $5,000,000 may be laid by in that manner. But the greatest variation between the production and the manifested export was caused by the custom, common among passengers bound eastward, of carrying their dust or coin on their persons, so that no one knew how much they took. Thus there is no manifested export for 1848, and less than $5,000,000 for 1849, and less than $28,000,000 for 1850, while the aciual production and exportation of those years was about $100,000,000. We can safely put down the amount carried away in sixteen years unmanifested at $200,000,000, and by this calculation we shall have a total production of about $1,000,000,000, from the coast up to the end of 1865. Of this sum all has come from the mines of California, save about $100,000,000 contributed by Nevada, Idaho, Oregon, Arizona, Washington, and British Columbia. The accounts, however, of the contributions from these States and Territories have not been accurately kept, with the exception of Nevada, so it is impossible to give any precise statement of them.
3.- RECEIPTS FROM NORTHERN AND SOUTHERN MINES. The express company of Wells, Fargo & Co. transport nearly all the treasure produced on the coast, and they could, from their books, show the shipments of coin and bullion from every large mining town west of the Rocky mountains; but they have considered it advisable to allow the publication of the receipts of treasure at San Francisco only from the principal districts since 1860.
The following table shows the receipts of treasure, coined and uncoined, from the northern and southern mines of California :
Of the treasure thus received at San Francisco, about $4,000,000 annually is in coin, leaving the remainder to indicate the value of the dust and bars.
The “ northern mines,” as mentioned in the above table, include all those districts which send their treasure to San Francisco by way of Sacramento, or, in other words, all the interior of the State north of latitude 38° 30', while the s southern mines" include those districts which send their treasure by way of Stockton. To express it differently, the term “northern mines," as here used, means the counties Siskiyou, Shasta, Trinity, Plumas, Butte, Lassen, Sierra, Yuba, Nevada, Placer, EỈ Dorado, Sacramento, and parts of Calaveras and Amador; while the term “southern mines ” means Tulare, Fresno, Inyo, Kern, Stanislaus, Mono, Mariposa, Tuolumne, and parts of Calaveras and Amador. The extension of the railroad from Sacramento to the vicinity of Placerville, in 1863 and 1864, drew to Sacramento some trade that previously went to Stock
The receipts from the southern mines show a marked and steady decrease. During the first nine months of 1866 the receipts from the southern mines were $3,418,436.
Receipts from Nevada and the northern coast.
The “northern coast” means those mines which send their treasure to San Francisco by ocean steamers plying to ports of Northern California, Oregon, and Vancouver island. The term " · foreigh ports” excludes Victoria, and includes Mazatlan, Guaymas, La Paz, Honolulu, China, and Japan. San Francisco stands on a long peninsula, and all the traffic with the gold and silver mining regions is done across water. The yield of the northern mines is brought by the Sacramento steamers; the yield of the southern mines by the Stockton steamers; the yield of the northern coast by the northern coast steamers, and the imports from foreign ports are brought by other vessels.
The sources of the receipts are classified according to the vessels in which they are brought. These receipts are, however, not all in the precious metals as they come from the mines and mills, but portions are in coin.
Thus the coin included in those receipts was $9,363,214 in 1861, $5,593,421 in 1862, $6,383,974 in 1863, $5,743,399 in 1864, and $4,961,922 in 1865. No accounts have been kept of the coin sent to the interior ; but all this coin received must have gone from San Francisco, which has the only mint of the coast, and is the point at which nearly all the passengers and treasure arrive.
4.-COMPARISON OF RECEIPTS AND EXPORTS.
The following figures show the exports, the receipts, and the difference between exports and receipts for the last five years :
The total amount of coin receipts for the five years was $32,045,928; and the excess of receipts over exported during the same period was $25,952,655. A large part of the coin received must have belonged to the regular circulation of the country, going and coming with the current of trade. The receipts of treasure at San Francisco during the first nine months of 1866 were $3,000 less than in the corresponding period of 1865. The
year 1862 was unfavorable to mining in California because of a great flood, and 1863 because of a great drought; and some special unexplained influence may have operated to reduce the production and shipment in 1865 ; but the annual gold yield of California cannot now be safely estimated at more than $27,000,000. Several millions of each year's produce of the precious metals may be retained on the coast for purposes of currency, ornaments, and tableware.
The yield of the quartz mines is increasing slowly, as we know by the general testimony of the miners and by the increase of quartz mills; but there are no statistics to show the rate of increase. Although some mines have paid steadily at about the same rate for the last ten years, the business generally is very uncertain. Thus it appears from a report made by Mr. Rémond, State geological surveyor, that of sixty-three mills built in Tuolumne and Mariposa counties, between the Merced and Stanislaus rivers, thirty-eight were not running when he visited them between August and November, 1865, and in many
instances the veins had ceased to yield quartz rich enough to pay. And so it is in every part of the State where quartz mills have been built-a considerable portion of them have been abandoned as very unprofitable investments. And yet every week new and valuable veins are discovered, and they cannot be left unworked; and though many quartz miners fail, yet othets are deriving princely revenues from their claims.
Grass valley, the chief centre of the quartz mining of California, is becoming richer every year. It is safe to estimate that the capital invested in quartz mines and mills is yielding an average profit of twenty per cent. per annum, and that the average yield is at least three dollars per day for the men regularly at