under the heading of Gold. The average price of silver during 1914 was 54.8¢ per ounce at New York:

*Merced and Stanislaus combined to conceal output of a single dredge in each.

The value of the silver produced in California each year since 1887, is as follows:

*Estimate. See supplement at end of this chapter, pp. 33, 34.

Tungsten.

Reference: Bulletins 38, 67.

Tungsten, which is used in the steel industry and in the manufacture of electrical appliances, is produced by a few operators in California. Most of the California tungsten ore is scheelite, though wolframite and hübnerite also occur. The value of the ore is based upon the content of tungstic trioxide (WO), and quotations are commonly made per unit of WO, present. In 1914 there were mined 4,830 tons, valued at $180.575, which is a decrease from the previous year.

3

The annual value of tungsten produced in California since the inception of the industry is given herewith:

Reference: Bulletin 67, "Cassiterite."

Tin is not at present produced in California; but during 1891-2, there was some production from a small deposit near Corona, in Riverside County, as tabulated below. Small quantities of stream tin have been found in some of the placer workings in northern California, but never in paying amounts.

No commercial production of vanadium has been made in California. Occurrences of this metal have been found in the southeastern portion of the State and two companies have done considerable development work recently in the endeavor to open up paying quantities. Ore carrying the mineral cuprodescloizite and reported as assaying 4% V2O, is being developed at Camp Signal, near Goffs, in San Bernardino County. There is a growing demand for vanadium, for use in the steel industry.

Zinc.

Reference: Bulletins 38, 67.

Zine was produced principally in Inyo County during 1914, to the amount of 399,641 pounds, valued at $20,381, which is a very marked decrease from the production of 1913.

Total production figures for zinc output of the State are as follows:

SUPPLEMENT TO METALS PRODUCTION.

As noted under Gold in the foregoing pages, in order not to delay the issuance of this bulletin, the output of gold, platinum and silver was estimated, the final figures not then being available. In the interim, however, and subsequent to the main portion of this report being put into type, the data have been completed and received from the United States Geological Survey, through the courtesy of Mr. Charles G. Yale, Statistician in charge of the San Francisco branch office of the Division of Mineral Resources. Anyone wishing fuller details of the production of these metals may obtain the same by applying to the U. S. Geological Survey, Washington, D. C., for a copy of the "separate" on the subject.

*Combined to conceal output of a single dredge in each county.

GOLD SUMMARY.

The total gold produced in California in 1914 was 999,112.95 fine ounces, valued at $20,653,496, as compared with 987,186.59 fine ounces valued at $20,406,985 in 1913, or an increase of 1.21%. With the exception of 1883, this is the largest production of any year since 1864. The "deep" or quartz mines of the State yielded 559,826.79 fine ounces of gold, valued at $11,572,647. Of the deep mine gold 541,743.92 fine ounces valued at $11,198,841 was derived from siliceous ore; 16,630.14 fine ounces, valued at $343,776, was derived from copper ore; 35.37 fine ounces valued at $731 from lead ore; 71.69 fine ounces valued at $1,482 from silver ore; and from silver-lead ores 1,345.65 fine ounces valued at $27,817.

The placer yield of gold in 1914 was 439,286.06 fine ounces valued at $9,080,849. Of this $702,884 was derived from 105 hydraulic mines; $7,783,394 from 60 dredges; $329,948 from 70 drift mines and $264,623 from 105 surface or sluicing mines. The placers produced 43.97% of the total gold yield for 1914, and the deep mines 56.03% as compared with 43.30% and 56.70% for placers and deeps respectively during 1913. The dredges in the State produced 37.69% of the total gold yield from all sources in 1914, or 85.71% of the total placer gold.

SILVER SUMMARY

The yield of silver in California in 1914 was 1,471,859 fine ounces valued at $813,938, an increase in quantity of 93,460 ounces, but a decrease in value of $18,615. The larger portion of the output, or 1,267,752 fine ounces valued at $701,068, was derived from crude smelting ores. The largest production of silver came, as usual, from Shasta County from the smelting of copper ores. Inyo County follows Shasta, with a yield of 466,575 ounces valued at $258,016, derived from silver-lead ores. The silver obtained with gold in placer mining in the State in 1914 was 34,877 fine ounces valued at $19,287. The silver recovered by amalgamation in association with gold in quartz ores was 84,421 fine ounces valued at $46,685. The production from concentrates treated at custom mills and smelters was 22,444 fine ounces valued at $12,411.

CHAPTER FOUR.

STRUCTURAL MATERIALS.

As indicated by this chapter heading, the mineral substances herein considered are those more or less directly used in building and structural work. California is independent, so far as these are concerned, and almost any reasonable construction can be made with materials produced in the State. This branch of the mineral industry for 1914 was valued at $14,469,981, showing a decrease from 1913 like many other lines, owing to the financial depression. Only a few years ago its value was of no significance in considering the total mineral production of the State. With the growth, in population and otherwise, of California, this subdivision of the mineral industry in the State will increase indefinitely. Deposits of granite, marble and other building stones are distributed widely throughout the State, and slowly but surely transportation and other facilities are being extended so that the growing demand may be met. The largest single item, cement, has an unparalleled record of growth since the inception of the industry in California twenty-three years ago. Not until 1904 did the annual value of cement produced reach the million-dollar mark. It increased 500 per cent in nine years. Crushed rock production is yearly becoming more worthy of consideration, due to the strides recently taken in concrete building, as well as to activity in the building of good roads. Brick, with an annual output worth over $2,000,000, is slowly decreasing, due to the popularity of cement and concrete; nevertheless, this item will be an important one for many years to come, and of course, a market for fire and fancy brick of all kinds will never be lacking.

The following table gives the comparative figures for the value of structural materials produced in California during the years 1913 and 1914. Forty-four counties contributed to this total, and there is not a county in the State which is not capable of a considerable output of at least one of the following classes of material.