california's production of structural 

 and Industrial Materials. 



ALIFORNIA produces forty-seven mineral substances that broadly 

 may be classified as structural, industrial and commercial mate- 

 rials. The strictly mineral or metallic substances produced are 

 gold, silver, copper, quicksilver, making the total number of sub- 

 stances fifty-one. The aggregate values of all these fifty-one 

 mineral substances for the seventeen years beginning with 1887 

 and ending with 1903, are $418,851,833. 



Thirty-seven strictly structural and industrial materials produced by 

 California in the last seventeen years aggregate in value $54,767,164. 



These thirty-seven substances are: Antimony, asbestus, cement, 

 chrome, chrysoprase, clay (brick), clay (pottery), fullersearth, granite, 

 graphite, gypsum, infusorial earth, iron ore, lead, lime and limestone, lithia 

 mica, macadam, magnesite, manganese, marble, mica, mineral paint, onyx, 

 and travertine, paving blocks, platinum, pyrites, quartz crystals, rubble, 

 sand (glass), sand (quartz), sandstone, serpentine, slate, soapstone, soda, 

 sulphur. 



In the year 1887 the substances produced numbered twenty-one, val- 

 ued at $2,948,251. In 1903 thirty-nine substances were produced, valued 

 at $16,913,381. 



Those that did not fail of production during the seventeen years are: 

 Asphalt, bituminous rock, borax, pottery clay, coal, gypsum, granite, lead, 

 magnesite, manganese, marble, mineral water, petroleum, salt, sandstone. 



Cement was not produced commercially in California until 1891. The 

 product that year was 5000 barrels, valued at $15,000. With the excep- 

 tion of 1893 there has been an annual product since 1891, which in 1903 

 had increased to 640,868 barrels, valued at $968,727. 



Pottery clays, including materials employed in the manufacture of 

 terra cotta ware, while improving in value, have not shown an appreciable 

 increase in quantity. In 1875 the output was 75,000 tons, which increased 

 to 100,000 in 1890 and decreased to 24,592 tons in 1897. But with the 

 decrease in the quantity recorded there v/as an increase in value from an 

 average of 50 cents per ton to $1.00 per ton; and from that year a steady 

 increase in quantity (and maintenance of value) to 90,972 tons in 1903. 



The production of granite made the largest showing from 1889 to 



1892, averaging more than one million dollars a year and totaling for the 

 four years $4,829,018. In the past five years there has been an increase 

 in granite production to $678,670 in 1903. 



Magnesite production increased from 600 tons in 1887 to 4726 tons 

 in 1901, but decreased to 2830 tons in 1902 and 1361 tons in 1903. 



Marble increased in production in the seventeen years from $5000 to 

 $97,354. The largest production was in 1892, when the values reached 

 $115,000. From that year the production was variable until 1902, when 

 there was an increase from 2945 cubic feet of the previous year to 19,305 

 cubic feet. 



The production of soda was not begun until 1894. In 1903 only the 

 production of crude soda was recorded, amounting to 18,000 tons. Prices 

 for the refined soda in the ten years varied from $25 to $50 a ton. The total 

 production for the ten years was 62,430 tons, valued at $1,173,500. Im- 

 ports in 1903-1904 amounted to more than 6000 tons. 



Asphalt and bituminous rock showed a total combined production of 

 884,746 tons, valued at $5,914,667. Asphalt gave the smallest returns, 

 $16,000, in 1887, and the largest, $503,659, in 1903. The smallest out- 

 put of bituminous ro*k was recorded for 1902, $43,411, and the largest In 



1893, $192,036. 



