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many rich specimens have been obtained is indubitabile. All the work in the mine, except on rare occasions, is done by two partners in it, and strangers are not permitted to enter. The rich deposit is found in streaks near the walls. The mine is opened by a tunnel 225 feet long. The mine owners say the whole hill will pay—the rock for crushing and the gravel for washing.
The first extension of the Green Emigrant on the north is 600 feet long, and is being opened or examined by cross cuts. Some auriferous talcose slate has been found, but so far no vein. Monahan & Co. have 2,000 feet on the same vein, and have done nothing.
The Wells claim is 2,400 feet long, and the vein is five feet wide. There are two shafts, one 50 and the other 40 feet deep. Forty tons have been crushed, and they yielded $12 50 per ton on an average, after the specimens had been picked out.
The first extension south of the Green Emigrant is 2,000 feet long. A shaft has been sunk 25 feet, and the vein is 18 inches wide. The rock prospects well.
NEW YORK AND EMPIRE.—The New York mine, formerly known as the Conrad, one mile west of Auburn, has three veins, each two feet wide, not more than 200 feet apart.
The Empire Company, at Ophir, has 11,000 feet of claims on various veins, and is working in a shaft 35 feet deep, in a vein two feet wide. The milí has 10 stamps, and began to run in March of this year. The average yield is 88 per ton, exclusive of the sulphurets, which are not saved. An experiment was made in tliis mill of working the float quartz, which covers the whole country near Ophir, but it did not pay. The working vein is in granite and runs north and south. The mill was burned down in July, after it was visited.
SCHNIBLE.—The Julianne or Schnable mine, on Jenny Lind Flat, near Ophir, is 2,000 feet long on a vein two and a half feet wide, running north and south in granite, and dipping 80° to the east. A shaft has been sunk 105 feet, and drifts have been run 50 feet below the surface, 1,200 feet on the vein, in pay all the way. The pay is evenly distributed through the vein, and the average yield of free gold, as reported by the proprietor, is $6 per ton; but the general impression in the neighborhood is that the mine is quite valuable. The expense for stopping out is $2 per ton, and the total expense $4. The croppings have paid for 2,000 feet on the surface. The rock contains seven per cent. of sulphuTets, which assay $147 per ton, or $10 per ton of rock. There is a five-stamp mill which has been running for two years and a half, working 25 or 30 tons per week.
WALTER AND ST. LAWRENCE.—The Walter mine, 900 feet, at IIamberg Flat, is on a vein which runs northwest and southeast, averages 18 inches in thickness, and dips 80° to the southwest. A shaft has been sunk 45 feet, and drifts have been run 48 feet on the vein in pay rock all the way. There is slate wall on both sides, but in some places the granite comes to the west wall. Some very rich specimens have been found. The mine has no mill. Twenty tons bave been crushed, and the yield was $13 per ton.
The St. Lawrence Company has three claims. The St. Lawrence vein, on Thich they are working, runs northeast and southwest, dips southeast 65°, and is 20 inches wide. The claim on this vein is 1,400 feet long. A shaft has been sunk 75 feet, and drifts have been run 85 feet in pay all the way. The walls are granite, with a slaty gonge about an inch thick on each side. The surface was worked with a profit by Mexicans for many years. The St. Lawrence claim on the Boulder vein is 2,400 feet long. The vein is three and a half feet wide, and has the same conrse, dip, and walls as the St. Lawrence. A shaft has been snnk 75 feet, and drifts have been run 75 feet. An assay of the sulphurets shows $138 gold and $158 silver per An assay of dry slum showed $19 gold and $46 silver per ton.
GOLDEN RULE.— The Golden Rule Company, of Sacramento, (to be distin
guished from the Golden Rule Company of San Francisco, which has a valuable mine on the Mother lode in Tuolumne county,) has claims, each 2,000 feet long, on three parallel veins nine miles south-southwest of Auburn. The eastern vein is three feet thick, and has been opened by a shaft 250 feet deep and drifts 160 feet long on the vein, all the way in rock that averages $12 to the ton. The middle vein is two feet thick, and the rock averages $8. This is 100 feet from the eastern vein, has been reached by a cross-drift from it, and a drift in the vein has been run 60 feet. The western vein is 60 feet distant, is fifteen inches wide, and has been opened to a depth of 75 feet by a shaft, and to a length of 50 feet by drifts. The eastern and middle veins show quartz of the same quality; the western has a bluish hard quartz, containing more free gold than the others, which have white quartz and sulphurets. A 20-stamp mill is going up, and also a reverberatory furnace, with a capacity to roast a ton at a charge. The sulphurets are to be concentrated with Hungerford's concentrator. There is a 75-horse power steam engine and steam hoisting works. For hoisting, a flat wire rope
is used. STEWART'S FLAT, AMERICAN BAR, AND DAMASCUS.—Stewart's Flat mine, 1,350 feet long, is on a vein two and a half feet wide, running north-northeast and south-southwest, in granite walls. A shaft has been sunk 120 feet, and drifts have been run 380 feet on the vein in pay all the way. The average yield is $15 per ton. The mine was worked from 1862 to 1864, and was then left idle till this spring, when work was resumed. There is a five-stamp mill.
At American Bar, two miles below Michigan Bluff, a quartz mill is being built.
The Damascus quartz mine, at Damascus, was worked for three years, paying a profit part of the time, and has been idle for the last three years. The vein is 12 feet wide and the mill has five stamps.
RED STONE.—The Red Stone, 10 miles north of Dutch Flat, on the north branch of the north fork of the American river, is 2,400 feet long, on a vein which runs northwest and southeast, and is five and a half feet wide, between granite and talcose slate. A depth of 165 feet has been reached, and drifts have been run 30 feet in the vein. The rock, so far as examined, is very rich. A fourstamp mill has been running, and an 18-stamp mill is now in the conrse of erection. There is a mill of two stamps erected in Bear Valley, for the purpose of
prospecting the Champion and tho Blue Belle lodes, both of which yield excellent quartz.
Canada HILL.-Canada Hill, on the Forest Hill ridge, 10 miles west of the sunimit, has a number of quartz lodes, some of which are very promising at the surface. The gulches about the hill are full of rough gold and gold-bearing quartz. Most of the miners there are Mexicans. The Secret mill, built four years ago, ran two years and is now standing idle.
The Buena Vista Company are opening a quartz claim.
Bald Mountain, two miles east of Canada Hill, is covered with float-quartz, and many of the pieces contain specks of gold plainly visible. There has been much prospecting for lodes, but none of any size have been found.
HARPENDING MINE.— The Gold Quarry Company's property, familiarly known as the Banker or Harpending mine, is situated near Lincoln, on a deposit similar to that of Quail Hill, in Calaveras county. The ores are delivered by ontract at 40 cents per ton. A 40-stamp mill is at work, crushing about five ons daily to the stamp. The labor is principally Chinese. The estimated cost of the entire extraction and treatment is within $1 per ton.
Professor Silliman, in a paper on the Harpending and Quail Hill deposits. says:
Accompanying the entire mass of decomposition at both localities, occur both gold and silver, disseminated with remarkable uniformity in all parts of the ore ground. At Whiskey Hill films of metallic silver are visible upon the talcose masses, stained green by malachite
or chrysocolla. The gold is rarely seen in situ, being mostly obscured by the very rusty and highly-stained character of the associated materials. But it is rare that, on washing a small quantity of any of the contents of these great deposits, gold is not found in angular grains or small ragged masses, from the size of a few grains' weight to impalpable dust. Nuggets of several pennyweights occur occasionally. This gold has evidently accompanied the sulphurets and been left in its original position and condition by their decomposition. There can be little doubt that the gold of the gulches adjoining these deposits has been derived from them. At Whiskey Hill the gulch gold ceases to be found as soon as the limits of this deposit are passed ; and the same is true at Quail Hill. The occurrence of deposits of this nature throughout the range of the foot hills seems to offer the best solution which has suggested itself of the origin of the placer gold, which is found in situations so far removed from the gold belt of the upper sierras, and away from sources usually recognized as those to which placer gold may be referred.
The chemical results of the extensive decomposition of metallic sulphids which has in former times occurred at these localities offer an interesting problem in chemical geology: The sulphur has been removed chiefly as sulphuric acid, beyond doubt, which has combined with iron and copper to form sulphates of those metals. These have, for the most part, disappeared, being washed out by the atmospheric waters, and have followed the drainage of the country. At Whiskey Hill I found the sulphate of iron, (coquimbite,) sulphate of copper, (cyanosite,) and alum. Tbe water of the shaft contains copper enough to redden the iron tools.
From all the evidenco presented, we seem justified in regarding these remarkable metallic deposits as segregated veins, holding a pretty uniform and high tenor of gold and silver, associated with and derived from the decomposition of extended masses of metallic sulphurets and quartzose matter, and carrying, at times, ores of copper, the commercial value of which is, however, entirely subordinate to that of the precious metals wbich are found to ebaracterize these veins or ore channels.
Nevada county, California, has for its eastern boundary the dividing line between California and Nevada State; extends across the summit and down the westerly slope of the Sierra Nevada mountains to the foot hills that border the eastern edge of the Sacramento valley. Its northerly and southerly boundaries are the Middle Yuba and Bear rivers, to the sources of those streams; thence due east to the State line. Its length from east to west is about 65 miles, having an average breadth of 20, and containing about 1,300 square miles. It is near the middle of the great gold region that stretches along the westerly slope of the mountain chain, extends entirely across the auriferous belt, and in the last nineteen years has produced more gold than any tract of country of equal extent in the world.* The elevation above the level of the ocean ranges from 800 to 1,000 feet, along the foot hills, and rises to 8,000 and 9,000 feet in places on the summit, thus affording a great variety of climates. On and near the summit the ground is covered with snow for more than half the year, while at the foot hills snow and ice are seldom seen.
Several streams, which have their sources high up in the mountains, flow westerly through the county, and empty into the main Yuba or Bear river. The most considerable of these are the South Yuba, Deer creek, and Greenhorn, which, with their tributaries, have cut deep channels in the primitive rock. Between these streams and those forming the northerly and southerly boundaries
* Professor B. Silliman says of the product of the valley district:
“ The place has obtained a well-earned celebrity as the most prosperous of all the gold quartz-mining districts in California. Quartz mining was begun here as early as 1850, and has been continued, on the whole, with a steadily increasing success, to the present time.
* It is difficult to obtain exact statistics of the total product of the Grass Valley quartz mines, but it is believed by those best able to form a trustworthy opinion on this subject that the product in 1866 was probably not less than $2,000,000, while for the whole period from 1851-say 14 years—it was probably in excess of $23,000,000.”
of the county are four main ridges running nearly at right angles with the mountain chain, and varying in length from 25 to 40 miles. These ridges are composed mainly of gravel and alluvial deposits, the debris from the higher mountains, and matter of volcanic origin. In places the bed rock rises nearly to the surface, but in general the alluvium is from 100 to 200 feet in depth, and at the higher elevations is covered with basaltic rocks and a deep volcanic cement. The volcanic covering is supposed at one time to have extended over a much larger area than at present, forming extensive table lands, but in course of time has been worn away on the lower portions and along the margins of the ridges, leaving the alluvium as the upper surface, and which now constitutes the principal field for hydraulic mining *
* Professor Silliman, in an article published in Bean's Directory of Nevada, says of the general geological character of the Grass Valley district:
“The gold-bearing rocks at this place are mostly highly metamorphic schists or sandstone passing into diorite or greenstone syenite. These greenstones, seemingly crystaline, are probably only highly altered sedimentary rocks, containing a large amount of protoxide of iron with sulphuret of iron. In some parts of the district slaty rocks occar, more or less talcose or chloritic in character; masses of serpentine also abound, forming at times one wall of the quartz veins. This serpentine is probably metamorphic of the magnesian rocks last named. The red soil, seen almost everywhere in the Grass Valley district, has its origin from the peroxidation of the iron contained in the greenstones and diorites, and set at liberty by its decomposition.
" The line of contact between the gold-bearing and metamorphic rocks of Grass Valley and the granites of the Sierra Nevada is met on the road to the town of Nevada, about a haif mile before coming to Deer creek. The talcose and chloritic slates are seen to the north, in the direction of the Peck load, and in the slate districts of Deer creek.
“ The dip and strike of the rocks in the Grass Valley region is seen to vary greatly in different parts of the district. Following the course of Wolf creek, a tributary of Bear river. it will be observed that the valley of this stream-which is Grass Valley—as well as of its principal branches, follows, in the main, the line or strike of the rocks. In the absence of an accurate map of the region it may not be easy to make this statement evident, But all who are familiar with the chief mines of this district will recall the fact that the course of tbe veins in the Forest Springs location, at the southern extremity of the district, is nearly north and south-N. about 20° E.—with a very flat dip to the east; while at the Eureka mine, on Eureka Hill, about four miles to the northward, the course of the vein is nearly east and west, with a dip to the south of about 78 degrees. Again, commencing at North Gold Hill and following the course of the famous vein which bears the names of Gold Hill, Massachu. setts Hill, and New York Hill, we find the veins conforming essentially to the southerly course of the stream, with an easterly dip. The North Star, on Weimar Hill, has likewise the same general direction of dip. Near Miller's ravine, at El Dorado mill, Wolf creek makes a sudden bend to the left or east, leaving the Lone Jack, Illinois, Wisconsin, and Allison Ranch mines to the west. All these last-named mines are found to possess a westerly dip, showing the existence of a synclinal axis running between the base of New York Hill and the mines having westerly dips last named, along which, probably, the veins will, if explored in depth, be found in basin. The dip at Lone Jack is about 30° west; at Allison Ranch it is about 45° west. Just below the Allison Ranch mine Wolf cieek again makes a sharp turn to the left; nearly at a right angle, and then resumes its former course with the same abruptness. A miie lower down, where it strikes the Forest Springs locations, we find the Morambagua inclosed in syenitic rocks, dipping at a very low angle to the east; a dip is seen also, at a still less angle, in the Shamrock, yet further south. There is probably a saddle or anticlinal axis below the Allison Ranch mine, due to the elevation of the syenitic mass, which, it seems probable, sets in at the sharp bend in the stream, before alluded to, and where the Tavine trail joins it. The stream probably runs pretty nearly in the basin of the synclinal.
“The rocks on the east side of Wolf creek, and above Forust Springs locations, dip westerly. Such is the case at Kate Hayes and with the veins on Osborn Hill. The middle branch of the creek sweeps around to the east, forms its junction with the north fork, and the veins explored there near its upper waters, as at Union Hill, the Burdette ground, Marply vein, Lucky, and Cambridge, all dip southwest or south, conformably to the Idaho and Eureka, and at a pretty high angle. The Eureka vein, going west, faults in the Whiting ground, and, having previously become almost vertical, has, west of the fault, a northerly dip at a high angle. At the Coe ground this northerly dip is also found at an angle of about 500. At Cincinnati Hill the vein dips southerly, in a direction exactly opposite to that of the North Star, there being a valley between the two, and a saddle or anticlinal betwcen Cincinnati and Massachusetts Hills.
* These facts, which by a more detailed statement could be easily multiplied, secm to warrant the conclusion that the course and dip of the Grass Valley veins is especially conformable
The whole country was originally covered with magnificent forests, the different varieties of the pine predominating in the more elevated regions, and giving place to the oak in the foot-hills. As the first settlers had no interest in the soil, and felt that they were but sojourners for a time in the mines, the timber has been wastefully used, and much of it has disappeared.
The entire county is what might be termed mineral land, as distinguished from agricultural. Yet there are many sheltered valleys of rich, arable soil which have been cultivated, and amply rewarded the husbandman. The largest of these is Pema valley, lying near the westerly border of the county, and containing about 2,000 acres of good soil, which has been occupied and cultivated for many years.
SETTLEMENT.— The first settlement in what is now Nevada county was made in the summer of 1848, when the south and middle branches of the Yuba were prospected for gold for a considerable distance into the mountains, and many to that of the rocks, and that the streams have, in general, excavated their valleys in a like conformable manner."
In reference to the gold-bearing veins of Grass Valley, Professor Silliman says:
** The quartz veins of Grass Valley district are not generally large. Two feet is probably a full average thickness, while some of the most productive, and those which have given from the first a high reputation to this region, have not averaged over a foot, or possibly eighteen inches in thickness. There are some exceedingly rich veins, which will hardly average four inches in thickness, and which have yet been worked at a profit, while at the same time there are veins like the Eureka, which have averaged three in thickness, and the Union Hill vein over four feet. The Grass Valley veins are often, perhaps, asually imbedded in the inclosing rocks, with seldom a fuccan or clay selvage or parting, although this is sometimes found on one or both walls.
** The walls of the fissures and the contact faces of the veins are often seen to be beautifully polished and striated.
“ The veins are, as a rule, highly mineralized, crystalline, and affording the most unmistakable evidence of an origin from solution in water, and afford not the least evidence of an igneous origin. Calcedonic cavities and agatized structure are very conspicuous features in many of the best characterized and most productive of the gold-bearing veins of this district. These indisputable evidences of an aqueous origin are seen in Massachusetts Hill, Ophir Hill, Allison Ranch, Kate Hayes, and Eureka.
“The metallic contents of the Grass Valley veins vary extremely ; some carry but little or no visible gold or sulphurts, although the gold tenor is found in working in mill to be satisfactory, and the sulphurets appear on concentrating the sands from crushing. This is the case in the Lucky and Cambridge mines, for example. But in most cases the veins of this district abound in sulphurets, chiefly of iron, copper, and lead, the sulphureted contents Farying greatly in the same vein; zinc and arsenic are found also, but more rarely, the most noted example of arsenical sulpburets being in the Norambagua and on the Heuston Hill; lead abounds in the Union Hill lodes, (as galena,) and the same metal is found associated with the yellow copper in parts of the Eureka mine. The gold when visible is very commonly seen to be associated with the sulphurets; this was particularly the case in Massachasetts Hill, while Rocky Bar and in Scadden Flat, on the same vein, the gold is found sometimes in beautiful crystallized masses, binding together the quartz, and almost destitute of sulpburets. Mr. William Watt informed me that in working some seventy thousand tons of rock from Massachusetts Hill vein, the average tenor of gold was about $80; but ut times this vein was almost barren, while again the gold was found in it so abundantly, especially where it was tbin, that it had to be cut out with chisels. It is matter of notoriety that in the Gold Hill vein, (continuation of the vein in Massachusetts Hill,) portions of the lode were so highly charged with gold that the amount sequestered by the miners in a single Fear exceeded $50,000. On the other hand, in the Cambridge and Lucky mines, having
a tenor of about $35 to $60 gold to the ton, the precious metal is seldom visible. In the Eureka, where the average tenor of gold in 1866 was $50 per ton, it seldom exhibited what may be called a 'specimen' of gold.
“The structure of the veins in Grass Valley varies in different portions of the district, especially in respect to the distribution of the pyrites and portions of the adjacent wall. On the Eureka Hill the veins possess a laminated structure parallel to the walls, enclosing portions of the diorite or talcose rocks, forming closures or joints in which the vein splits easily. On these surfaces of cleavage minute scales of gold may often be detected by close inspection. The sulphurets are also seen to be arranged in bands or lines parallel to the walls. In many other cases this kind of structnre is found to be wholly absent, while the sulphurets and gold appear to follow no regular mode of distribution. In a few mines the