PREFACE.

The State Mining Bureau is maintained for the purpose of assisting in all possible ways in the development of California's mineral

resources.

As one means of offering tangible service to the mining public, the State Mineralogist for many years has issued an annual or a biennial report reviewing in detail the mines and mineral deposits of the various counties.

The weak point in work of this character has been that the results of field investigations were so long in preparation that they had lost much of their usefulness by the time they finally appeared in print.

As a progressive step in advancing the interests of the mineral industry, publication of the Annual Report of the State Mineralogist in the form of monthly chapters was begun in January, 1922, and continued until March, 1923.

Owing to a lack of funds for printing, quarterly publication was begun in September, 1923.

Such a publication admits of several improvements over the old method of procedure. Each issue contains a report of the current development and mining activities of the state, prepared by the district mining engineers. Special articles dealing with various phases of mining and allied subjects by members of the staff and other contributors are included. Mineral production reports formerly issued only as an annual statistical bulletin are published herein as soon as returns from producers are compiled. The executive activities, and those of the laboratory, museum, library, employment service and other features with which the public has had too little acquaintance also are reported.

While current activities of all descriptions will be covered in these chapters, the Bureau will not discontinue its practice of issuing from time to time technical reports on special subjects. A list of such reports now available is appended hereto, and the names of new bulletins will be added in the future as they are completed.

The chapters will be subject to revision, correction and improvement. Constructive suggestions from the mining public will be gladly received, and are invited.

The one aim of the Mining Bureau is to increase its usefulness and to stimulate the intelligent development of the wonderful, latent resources of the State of California.

'Mining in California' is sent without charge to those on the Bureau's exchange list and to others who make written or verbal request.

Pages are numbered consecutively throughout the year and an index to the complete reports is included annually in the closing number.

In 1919-1920 the Mining Department was organized into four main geographical divisions, with the field work delegated to a mining engineer in each district working out from field offices that were established in Redding, Auburn, San Francisco and Los Angeles, respectively.

This move brought the Bureau into closer personal contact with operators, and it has many advantages over former methods of conducting field work.

To continue this system most effectively with the limited funds available for the next biennium, the Redding and Auburn field offices were consolidated and moved to Sacramento on June 1, 1923.

The boundaries of each district were adjusted and the counties now included in each of the three divisions, and the locations of the branch offices, are shown on the accompanying outline map of the state. (Frontispiece.)

Reports of mining activities and development in each division, prepared by the district engineer, will continue to appear under the proper field division heading.

Although the petroleum industry is but little affiliated with other branches of mining, oil and gas are among the most valuable mineral products of California, and a report by the State Oil and Gas Supervisor on the current development and general conditions in the state's oil fields is included under this heading.

Lassen County.

REDDING FIELD DIVISION.

W. BURLING TUCKER, Mining Engineer.

Corona Copper Mine. The property is situated near Milford, in T. 27 N., R. 14 E., southwest of Honey Lake, near the Lassen and Plumas County line.

The mine is being developed by Marr and Fex of Milford, and it is reported that a large body of copper ore has been exposed that runs from 2 to 15 per cent copper.

Shasta County.

American Mine, situated in Secs. 12 and 13, T. 33 N., R. 7 W., on the ridge north of Cline Gulch, 34 miles northeast of French Gulch. Elevation, 2800 feet. Owner, W. Frank, of French Gulch. Holdings consist of the following claims: American, Wheeler and Summit, totaling 100 acres of which 60 acres are patented. The property has recently been examined by engineers representing Comstock, Nevada, interests. It is reported that a bond has been taken on the property, and that active plans of development will be started in the near future, under the supervision of Harry M. Thompson, of French Gulch. Several men are employed in repairing the road to the workings which are located on the ridge north of Cline Gulch, between Clear Creek and J. I. C.

Gulch. The workings consist of tunnels at several elevations between 2500 feet and 3500 feet.

Bibliography: State Mineralogist's Reports VIII, pp. 564–565; X, p. 637; XII, p. 245; XIII, p. 349. U. S. Geological Survey Bull. No. 540, pp. 35, 60-61.

Lewis Gardella of Oroville, dredge operator, has purchased from the American Gold Dredging Company 310 acres of land on Clear Creek.

Highland Mine. The Iron Mountain Investment Company, a subsidiary to the Mountain Copper Company, has received a patent for the Highland Lode mining claim, in Sec. 35, T. 33 N., R. 6 W., in the Flat Creek Mining District.

The Mount Shasta Silica Company, of Weed, Siskiyou County, has purchased forty-six placer claims, known as the Insulator Group. These claims are located on a large deposit of diatomaceous earth in the northeastern part of Shasta County, near Bartle Station, on the Pacific Gas and Electric Company's railroad to Pit No. 1 power plant.

Silver Falls and Chicago Consolidated Mines, are situated four miles northeast of Igo, in the South Fork Mining District, in Secs. 17, 18, 19 and 20, T. 31 N., R. 6 W., at an elevation of 1400 feet. The property is under option to the California Bi-Metallic Corporation, L. G. Vinson, president; Paul Drinkwitz, secretary; Louis F. Eaton, general manager. Office, 21 Carrillo Building, Santa Barbara, California.

A detailed description of this property is to be found in the July chapter of Report XVIII of the State Mineralogist, pp. 316-317.

Active development operations were started by this company the latter part of October, 1922. Since that date, a total of 1400 feet of development work has been done, including raises, crosscuts and drifts.

Mine development: At 500 feet from the portal of the main tunnel level, drifts have been driven on the Pillchuck vein for a distance of 271 feet northeast, and to the southwest a distance of 50 feet. In the drift to the southwest the face shows 3 feet of mineralized quartz. It is stated that samples taken from the vein have an assay value of $25 per ton, in gold and silver. At the intersection of crosscut No. 36 and the drift on No. 28 vein, a raise has been put up on No. 28 vein for a distance of 155 feet, and then on an incline of 50 degrees west, and it has less than 250 feet to go on the incline to reach the surface. The vein as developed by this raise has a width of 6 inches to ten inches of mineralized quartz.

The drift on No. 28 vein has been extended 250 feet northeast. At about 380 feet from the raise a rich shoot of ore was encountered, showing from 8 inches to 2 feet of quartz. Samples taken from this shoot. are said to average $100 per ton, with $15 in gold. The main crosscut tunnel was extended 190 feet to vein No. 36. A crosscut was driven south from No. 27 drift 30 feet to vein No. 26, then drifted northeast on this vein 120 feet.

Surface development: In the Buckley tunnel, which is on the main Chicago-Madison lode, the drift on the vein has been extended 40 feet, making a total distance on the vein of 120 feet. The shoot of ore

developed on this vein is from 80 to 100 feet in length, 12 inches to 2 feet in width, and assays from it are reported to have a value of $65 in gold and silver per ton. About 340 feet northeast of No. 2 Wright shaft, at an elevation of 2000 feet, a tunnel is being driven north to cut the shoot of ore developed in the Buckley tunnel. This tunnel is in 80 feet, and will give about 250 feet of backs. At the collar of No. 2 Wright shaft a crosscut tunnel is being driven north to cut the main Chicago vein. The tunnel is now in 130 feet. At about 50 feet from the portal the tunnel cut two veins, which have widths of 12 inches to 18 inches, assaying $25 to $30 per ton in gold and silver. In the ore developed in the Buckley, and the tunnel from the Wright No. 2 shaft, the principal values are in gold, some assays showing as high as $65 in geld with $16 in silver.

Equipment consists of Type W. G. 6, 12" x 12" Sullivan compressor, capacity 365 cu. ft., driven by 50-horsepower Holt gas engine; high pressure blower, 12-inch outlet driven by 10-horsepower gas engine; Sullivan drill sharpener, 6 Sullivan air drills and 12 ore cars. Buildings comprise assay office, compressor house, blacksmith shop, two bunk houses, office and superintendent's residence. Twenty-five men are employed.

Bibliography: State Mineralogist's Report XVIII, pp. 313–317.

The Sybil Mine, which is located in Sec. 7, T. 33 N., R. 7 W., 5 miles northwest of French Gulch, recently suspended operations. The property is owned by the Shasta Mining Company of San Francisco, and has been under active operation for the past two years by Harry M. Thompson and associates of San Francisco, California.

The main working tunnel is driven southeast 700 feet at an elevation of 3700 feet. A winze was sunk from this level to a depth of 150 feet. At 80 feet below the tunnel a drift is driven 175 feet east, and 175 feet west on the vein.

Equipment consists of 12" x 12" Laidlaw-Dunn Gordan compressor, driven by 50-horsepower motor; 5-stamp mill, 1000 lb. stamps, and Frue vanner.

Bibliography: State Mineralogist's Report XIV, p. 777. U. S. Geological Survey Bull. No. 540, pp. 68–69.

Texas Consolidated Mine, which is situated in the Old Diggins Mining District, 9 miles north of Redding, is under lease and bond to Harvey Sallee of Old Diggins. The main working tunnel, known as No. 5 tunnel, is driven N. 10° E., 1600 feet and is 910 feet below the surface outcrop. The vein strikes N. 10° E. and dips 70° to the east, and where worked is reported to have been from 8 to 12 feet in width. The vein is faulted by a series of N. 40° W. faults, which cut off the ore. The present development work is confined to driving two crosscuts. on No. 5 level, one to the east and the other to the west, located beyond the winze sunk from this level, with the idea of picking up the ore shoot that was cut off by one of these N. 40° W. faults.

Four men are employed on development work.

Bibliography: State Mineralogist's Reports, X, pp. 629, 630; XI, pp. 43, 395-397; XII, p. 258; XIII, p. 365; XIV, p. 800.