descended, and at a depth of 40 to 60 feet, respectively, entered drifts, which showed a serpentine formation, in places impregnated by silicious infiltrations, and in the bottom drift there was a considerable showing of vein matter. Traversing the vein matter were numerous fragments of dark-colored silicious rock, of opal-like character; similar rock was seen on the dump of many of the workings. This rock is also quite common at Sulphur Creek, and although cinnabar is frequently found adhering to the cleavage faces of such fragments, it seldom penetrates the mass. The Elgin Quicksilver Mine. This mine is situated on the headwaters of the southwest branch of Sulphur Creek, about 3 miles northwest from the village of Sulphur Creek. A precipitous bluff, showing outcropping sandstone discolored by the heated waters of sulphuretted springs, here abruptly rises to the southwest of the creek. At various places on the bluff calcareous and silicious vein matter is conspicuous, and old workings therein have shown "pay ore." The principal and more recent workings are two tunnels, the lower of which is situated at the height of about 400 feet above the creek. This has been run for a distance of about 180 feet through vein matter, which is both silicious and calcareous. The silicious portion varies in color from white to almost black, and in texture from crystalline to amorphous or vitreous, and in structure from massive to "honey-combed." The calcareous vein matter also varies from crystalline to amorphous, occurring in some places as ribbon-like, and in others as stalactitic masses, the in latter form being common to both the silicious and calcareous vein matter. The best pay ore is said to be of the spongy silicious variety, which the cinnabar frequently penetrates the vesicular structure. A stream of hot sulphuretted water issues from the tunnel. The strike of the vein matter appears to be north of west and east of south; but as no definite wall is showing, the direction can scarcely be decided with certainty. About 110 feet from the mouth of the tunnel a drift has been run, probably 60 feet to the northwest, in vein matter. At the end of the tunnel a crosscut has also been made some 80 feet to the southeast and 60 feet to the southwest; at the end of the southeast portion a gouge about 3 feet in thickness shows to the west of the vein matter. The northwest portion of the crosscut, which has also been run in vein matter, is the source of the stream of hot water before mentioned. The temperature in this portion of the workings is very high, but the explorer is fully compensated by a glimpse at the process of vein making, which the place affords. The newly formed, colored crystalline minerals, dripping with heated water, sparkle as the light of the candle falls upon them, and at amidst many points in the face of the drift pure white stalactites grow the sulphuretted steam. Extending into the mountain amidst the vein matter beyond the breast of the workings, are several spaces yet unfilled with mineral, but the rocky walls inclosing them are lined with pure white aragonite, silicious incrustations, or yellow crystals of sulphur. About 100 feet eastward from the mouth of the lower tunnel the sand stone crops out, having a strike of southeast by northwest magnetic, and between the sandstone and the tunnel a silicious, iron-stained rock exposed. The upper tunnel is situated about 70 feet above the lower. This has been run in a westerly direction in vein matter, which shows much sulphur on the northwestern side of the working. At a distance of about 40 feet from the mouth of the tunnel, a hanging wall of shale, about 1 foot thick, capped by sandstone, was struck. From that point the tunnel was run along the hanging wall, the direction indicating the strike of the vein matter to be east of north and west of south magnetic. The total length of the tunnel is 110 feet. About 15 feet from the end of the tunnel a winze was sunk to a depth of 26 feet on the hanging wall, all the way in ore. The hanging wall in the winze shows a dip to the southeast magnetic of about 45°. Good pay is said to have been taken from this tunnel. Above the tunnel much sulphur is shown, as hereinafter noted. About 300 feet below the upper tunnel, and probably 2,000 feet to the southeast therefrom, there is a gas spring, which the writer was informed had been burning more than twelve months. The outcropping rocks near the spring are sandstone and shale, but the gas seems to come from silicious vein matter, similar to that observed in the Elgin Mine. The gås issued from a hole about 3 feet deep, and burned with a flame about 3 feet in height. Immediately above the gas spring, between croppings of sandstone, is a decomposed shale, which emits a fetid odor and inflammable gas when disturbed. The Clyde Gold Mine. The trail from the Elgin Mine to the Clyde is a somewhat steep ascent of about 1,000 feet, over a serpentine formation, which commences on the northern bank of Sulphur Creek. The Clyde is situated on a spur of the main ridge between Lake and Colusa Counties. This mine seems to be at the contact of the serpentine and a soft slate, or shale, traversed by numerous veinlets of quartz. Here a tongue of slate appears to stretch out into the serpentine from a main ridge of slate, which extends to the southeast. The formation to the north, northeast, east, and south from the Clyde Mine is serpentine, while to the westward slate prevails for several miles. The Clyde Mine has been known for more than twenty years as showing croppings of auriferous rock. About 1886-87 Mr. Haskin, who lived in Colusa, relocated the claim, and sunk a shaft to the depth of about 146 feet in the slate; he struck rich gold-bearing ore, which is said to have consisted of decomposed slate. The ore was worked in a 31-foot Huntington mill, and it is said that as high as $200 a day of twentyfour hours was "cleaned up," seven or eight men being employed. At a depth of 90 feet, a large quantity of pyrites was encountered, but the ore is said to have deteriorated. Drifts were made at the depth of 60 and 90 feet, in the hope of finding more rich ore, but the works are now caved in. In 1887 or 1888 the property was sold by Mr. Haskin to H. M. Cooper, of Williams, who, commencing at a slightly lower elevation than that of the old workings, ran a tunnel in a westerly direction for about 100 feet, with a crosscut and two small winzes. The formation is soft slate, or shale, traversed by veinlets of quartz; at one point several feet of serpentine was passed through. The tunnel is timbered. About three years ago a shaft was sunk on the Clyde claim, a short dis tance southeast from the old workings; it appears to be upon the contact of the serpentine and a steatitic clay. Much water was encountered and the shaft abandoned. A tunnel is now being run by Mr. Cooper in a northwest direction, about 100 feet below the level of the old workings, toward the contact of the serpentine and slate. The Keely Claim. This claim, which is situated about 100 yards southeast from the Clyde, was relocated by J. Hawkins, in 1891. Here disjointed masses of auriferous rock were found upon the surface of the ground, but none beneath. The dirt on the surface of the claim prospects a few colors to A shaft has been sunk on this claim, apparently through decomposed serpentine, but nothing of importance was discovered. A little below the Clyde Mine, a 5-foot Huntington mill was erected to work the ore on the Keely claim. About 150 tons of ore are said to have been worked, and about $700 to have been cleaned up. The writer was informed that the mill belongs to J. W. Brinn, of Bear Valley. The Manzanita Mine. This mine, which has been worked at intervals for nearly thirty years, was reopened in 1885 by the Manzanita Gold Mining Company, organized in New York. They erected a mill and commenced work upon the southern end of the claim. Their plant consists of three 5-foot Huntington mills, seven Victor concentrators, three 5-foot amalgamating pans, two 8-foot settlers, a No. 1 Gates crusher, and a sixty-five horsepower engine and boiler. The ore is crushed so as to pass a three-quarter round screen, and is pulverized so as to pass through a No. 8 slot screen. The richer ore, which averages $32 per ton, nearly all gold, with a very small amount of silver, is worked in the amalgamating pans. It is a free-milling ore, as described in the Bureau's report for 1888, but the gold is so exceedingly fine that the ore has to be ground until it will pass through a No. 80 mesh screen. There is also some bituminous matter with the ore, but it does not now seem to occasion any trouble. The lower grade ore, which runs from $1 to $2 per ton in free gold, is crushed and concentrated, and worked in the pans. The tailings from this ore seldom go over 25 cents per ton. The low-grade ore is worked principally in the summer, when it can be hauled the more easily to the mine. The richer ore is worked in winter. The work on this mine hitherto has been largely that of development, and consequently much low-grade ore has been handled. The manager states that there is a large quantity of low-grade ore in sight, which can be profitably worked, and some strata that are rich. As is well known, the Manzanita was first located as a quicksilver mine, and subsequently the gold value so exceeded that of the quicksilver that the mine was worked entirely for the gold: Under the present management an effort is being made to recover both metals. The ore from the part of the mine yielding the quicksilver is worked by the following method: It is first pulverized in the Huntington mill, then sized by a gravity sizer, designed by G. V. Northey, manager of the works, and then concentrated. Two concentrators work the coarse ore, two the medium, and one the slum. The concentrates average a gold value of from $100 to $200 per ton, and assay about 20 per cent in quicksilver. MANZANITA MINE, SULPHUR CREEK, COLUSA COUNTY. Photo. by W. L. Watts, Field Assistant. : The concentrates, which were being stored at the time of the writer's visit, will be retorted and the residues amalgamated. It is estimated that by this process ores which cannot be worked to a profit by any other method will show a fair margin of gain. The manager states that ore * running as low as one tenth of 1 per cent in quicksilver can be worked so as to clear expenses, leaving the gold as a profit. The sizer above referred to is a tank, fitted with a sloping floor. At the upper end, where the pulp and water are admitted, the tank is traversed by two partitions, which act as riffles to distribute the ore in the main body of the tank. A third partition, near the exit end of the tank, acts as a riffle and restrains the coarser particles, which escape through discharge pipes in the sides near the floor of the tank. The medium and fine particles are washed over into the last compartment, the fine escaping through a discharge pipe near the center of the end, and the medium through discharge pipes near the bottom. The ore, which was being worked at the time of the writer's visit, was mined from the foot of the mountain immediately behind the works. An open cut was here being made in a bank of what appeared to be broken angular fragments of argillite, interspersing a loose, white, pulverulent material. The formation appeared to be a decomposed talus from the mountain, but the Superintendent said it would pay to work. Ascending the hill immediately behind the works, the formation resembles an altered argillite, white to bluish in color, varying from silicious to clayey, and having a strike of west of north by east of south. The whole mountain side is evidently altered by the action of mineral waters. The ore is found penetrating the rock and in seams, which have a trend still more to the east and west than the strike of the formation. Bituminous matter, as before mentioned, is frequently found associated with the rock, yielding sulphides of iron and mercury. As a general rule, the quicksilver rocks have a definite trend, but the gold occurs indiscriminately. Much sulphur is found in some portions of these workings, occurring as crusts on the surface or as irregular masses in the rock. At the height of something less than 200 feet above the creek the formation passes into an altered conglomerate, which in places shows some cinnabar. Still higher up toward the top of the mountain the conglomerate gives place to sandstone, and considerable cinnabar has been found associated with a calcareous gangue. The strike of these calcareous veins is east of north by west of south. At several places in the higher portion of the mountain cinnabar can be found by washing alluvial soil. The summit of the mountain is about 2,000 feet above sea-level and probably 450 feet above Sulphur Creek. It commands an extensive view, showing the Elgin and the Clyde in range with the Manzanita, approximately northwest by southeast magnetic. The Central Mine. This claim was located by Messrs. Northey & York in 1891. It lies nearly parallel to and adjoins the Manzanita on the east. Four short tunnels have been run on this claim, the highest of which is situated about 600 feet above Sulphur Creek. These tunnels have been run in an altered serpentine, and two of them penetrate to unaltered serpentine, which appears to form the core of the mountain, cropping out at the The loose and altered rock shows summit and a short distance below it. much cinnabar, an average sample of which, it is said, yielded 1 per cent, while high-grade ore has been found in silicious seams. The Oriental Quicksilver Mine. This mine was first located in 1863, and worked from time to time up to 1877. In 1891, croppings of pay ore were discovered by G. T. and J. W. Farris, who located the claim and took out some ore. They state that they took out several samples of ore of from 30 to 40 pounds each, and on reducing these in small retorts they came to the conclusion that the unassorted ore, from a 4-foot pay streak showing into the ledge, would assay over 5 per cent in quicksilver, and that the assorted would go very much higher. They state that they were compelled to suspend operations, because the mine was found to be on land held under a homestead patent by J. S. Braine, of Arroyo Grande, San Luis Obispo County. When the property in question was visited by the writer, an open cut had been run in the mountain for about 20 feet, disclosing a vitreous and white pulverulent vein matter. The vein matter exposed appeared to be about 6 feet in width, the course being west of north by east of south. It is said that the vein matter shows well in the pan, and that some nuggets of rich ore have been found. Another tunnel was commenced about 40 feet below this working; it was run in a decomposed formation, and toward the end of it is said to prospect well. The Sulphur Creek Quicksilver Mine. This mine was located by W. E. York and T. Persons. It is situated on the south side of Sulphur Creek and on an elevation a little more than 200 feet above it. The strike of the formation is west of north by east of south magnetic, and the dip northeasterly at an angle of about 45°. The formation is soft and decomposed, and the ore is said to follow the white clayey seams which traverse it. The workings consist of a tunnel about 85 feet in length, and a soft, decomposed material in the breast of the workings is said to yield over 2 per cent of quicksilver. The Empire Mine. This mine is owned by W. E. York and T. Persons. It is situated on the south bank of Sulphur Creek, its southwest boundary being about 400 feet above that stream. The surface of the mountain on which this claim is located shows cinnabar by prospecting the alluvium and decomposed rock with a pan, especially at one point near the summit, where considerable vein matter is exposed. This claim extends to the south bank of Sulphur Creek, and joins the southeast corner of the Manzanita, where a tunnel has been run into the mountain for a distance of probably 150 feet, the direction being a little east of south magnetic. About 100 feet of this tunnel was run in 1873, and sufficient ore to obtain sixtythree flasks of quicksilver was reduced in a small retort belonging to the Buckeye Mine, which is distant about three quarters of a mile in a southeasterly direction. run all This property was relocated in 1890 by W. E. York and T. Persons, who continued the tunnel about 50 feet. This tunnel has been the way in vein matter, and pay ore is said to have been taken out in many places. The Mercury. This claim is situated in the Sulphur Creek Mining District, on the south side of the creek. It was located in 1890 by T. B. Persons of Sulphur Creek, who ran a tunnel of about 40 feet in length, and sunk several smaller prospect holes on the claim. Mr. Persons states that the workings appear to be all in vein matter. He concentrated several samples from his mine by washing, so that the ore was contained in about one twentieth the amount of rock, and he says that the samples so treated yielded about 10 per cent of quicksilver. Mr. Persons obtained altogether about 40 pounds of quicksilver from his samples. The Buckeye Mine. This mine is situated about half a mile southwest from the village of Sulphur Creek, on the eastern side of the ridge dividing Colusa and Lake Counties. As noted under Lake County, the Abbott Quicksilver Mine is on the opposite and western slope of this ridge. No work was being done on this mine at the time of the writer's visit. The property is owned by W. H. Shellback, of San Francisco. SULPHUR. In 1891 W. L. Bromley commenced mining sulphur on the Elgin property, about 4 miles northwest from the village of Sulphur Creek. As already mentioned, much sulphur was met with in the upper tunnel of the Elgin Mine. The sulphur deposits increase toward the summit of the mountain, where Mr. Bromley uncovered a large body of this substance. The sulphur occurs associated with decomposed rock, and at one point with soft white magnesite, and in many places the formation is permeated by hot springs. He first experimented with the "calcaroni " process. Owing either to the pulverulent nature of the gangue rock or errors in the construction, the "calcaroni" was not a success; the trouble being that the "calcaroni became "choked up," and the sulphur would not run. Another attempt was made by a Sicilian workman, who had operated the "calcaroni" process in Sicily. In this instance the sulphur burned up. Mr. Bromley then erected a furnace with three kettles, and commenced refining the richer ores, which yielded 30 per cent sulphur. His product, however, was black sulphur, and this was not acceptable in the California market, although containing 88 per cent of sulphur. In a sample of this product, which was examined by the writer, the dark color was occasioned principally by sulphide of iron and carbonaceous matter. SULPHUR NEAR WILBUR SPRINGS. At a point on the mountain to the northwest of Wilbur Springs, and about 200 feet above them, on the Moore property, sulphur was mined at an early day. The excavation shows altered serpentine and apparently an altered argillaceous sedimentary rock, some of which evidently contains a large percentage of sulphur. The outcropping rocks on the summit of the mountain are serpentine, while the loose rock in the excavation is for the most part whitish pulverulent and argillaceous, slacking on exposure to the air. The whole mountain's side has the appearance of being more or less altered by the action of mineral springs. There are also similar old workings at lower elevations.. COAL. In 1891, work was commenced by W. L. Bromley, on a coal prospect about 2 miles northwest from the village of Sulphur Creek. The formation is sandstone, with a strike of northwest by southeast. A tunnel, probably 100 feet in length, has been run to strike the croppings, which show coal of good quality interspersed with sandstone. From this formation casts of Aucella piochii were obtained, associated with the coal. A short distance from the above-mentioned tunnel, a prospect hole was also sunk upon coal croppings by E. Pardoe. A specimen of this coal was analyzed by Dr. W. D. Johnston, Chemist of the Bureau, and it showed the following composition: 7.00 per cent.. 29.75 per cent. 48.00 per cent. 15.00 per cent. 100.00 per cent. On a ridge to the south of the Enterprise Mine, and about 400 feet above Sulphur Creek, are outcroppings of limestone, showing numerous specimens of Rhynchonella Whitneyi. A similar formation crops out close to Wilbur Springs, and several years ago lime was burned there for local use. This limestone, when freshly broken, smells strongly of petroleum. As recorded in previous reports, inflammable gas and seepages of petroleum occur in this vicinity. BUILDING STONE. The O'Neil and Abbott Quarry. This quarry is situated on the Colusa and Lake Railroad, about half a mile east from Sites. It was opened in November, 1891, by Messrs. The stone is a O'Neil & Abbott, who leased the land from J. Sites. somewhat metamorphic sandstone, compact in texture and of grayish cast. It occurs in ledges 8 to 10 feet in thickness, dipping to the northeast at an angle of about 55°. The writer was informed that about ..$20,000 has been expended in developing the quarry. A mill with two gangs of saws for sawing the stone has been constructed, and the quarry is furnished with steam channelers, drills, and hoists. The developments at this quarry have shown the stone to be of uniformly good quality, and easily worked. This stone has found ready sale in San Francisco, Oakland, and elsewhere. The theater at Broadway and Thirteenth Street, Oakland, is built of it, and it is to be used in the construction of several other large edifices. Owing to the exceptional advantages of position and transportation, sawn stone can be delivered in San Francisco from this quarry at 60 cents per cubic foot. Along the strike of this formation are several points at which quarries might be opened to advantage. On the opposite side of Stone Corral Creek to that on which the O'Neil & Abbott quarry situated, a quarry has been opened by J. C. Sisk and R. S. Burgett. CONTRA COSTA COUNTY. By W. L. WATTS, Assistant in the Field. Mining in Contra Costa County is at present confined to the coal measures of Mount Diablo, where there appears to be still a large amount of coal which can be profitably extracted. During 1891-92, extensive alterations and improvements were made at the refinery of Messrs. Selby & Co., whose works are sufficient in themselves intimately to connect Contra Costa County with the mining interests of California. THE SELBY SMELTING WORKS. During the last two years important additions and improvements have been made at the works of this well-known company, which are situated on Carquinez Straits, near Vallejo Junction. A new lead refinery has been built, where a modification of the Parkes process is employed. A dust chamber and a 100-foot stack have been built, with which all the furnaces in the refinery are connected, instead of each furnace having its own chimney. A central stack and 300 feet of flue have been connected with the roasting furnaces, and the number of puddle-roasting furnaces have been increased from three to four. The three blast furnaces used by this company have also been connected with a 180-foot flue and dust chamber. The saving effected by these new flues and dust chambers has been estimated at about $15,000 a year. A condensing chamber has also been built for saving the sulphuric vapors arising from the parting department. This chamber is leadlined, its dimensions being 150x2x2 feet. Any vapor escaping from this condensing chamber passes into the 100-foot stack of the refinery. .The blast furnaces have a capacity of 60 tons each for twenty-four hours; they are furnished with separate tap holes for slag and matte, and a syphon tap with lead well for bullion. The slag is used for riprap work and extending the ore yard into the shallower portions of the straits. The matte is roasted and returned to the blast furnace, where it is smelted for second matte, containing about 40 per cent of copper. The second matte is roasted, pulverized, and used for making bluestone, together with the copper solution from the parting room, hereinafter described. The base bullion is treated in the softening furnace. The softening furnace is a reverberatory furnace, in which the bullion is subjected to a dark red heat without blast. Under these conditions the oxide of arsenic and antimony collect upon the surface of the bullion. oxide of arsenic is the first to form as a stiff scum, which is skimmed The off; next the oxide of antimony, which is also skimmed off. scums are too thin, quicklime is added to thicken them. If the scum is removed the process of softening is complete, and the resulting When the last |