Calcium arsenate was the leading product. Of the 17 manufacturers, 14 reported to the United States Geological Survey, and their figures check well with those compiled by the Bureau of Entomology, Department of Agriculture, which show a total production of about 34,000,000 pounds and a consumption of 31,000,000 pounds during the "cotton year," from September 1, 1922, to September 1, 1923. The unconsumed remainder was largely sold for use in proprietary mixtures, which were not manufactured. It went mainly to Georgia and South Carolina. This total production was equivalent to about 7,000 short tons of white arsenic. Lead arsenate was made by about 20 firms, 16 of which reported the production of 19,000,000 pounds of powdered lead arsenate, including a little of the compound reported as paste. This output required about 3,000 tons of white arsenic. Paris green, the aceto-arsenite of copper, was made by eight manufacturers, five of whom made about 3,500,000 pounds, requiring about 1,000 tons of white arsenic. A little Paris green was imported. Of sodium arsenite (weed killer) about 1,500,000 gallons was made which contained from 4 to 8 pounds of crude white arsenic to the gallon, requiring about 5,000 tons. Other arsenic compounds amounting to 8,500,000 pounds made by nine producers required 2,800 tons of white arsenic, most of which was converted into arsenic acid. Glass manufacturers used about 2,500 tons of white arsenic. The other compounds reported were cattle dip, magnesium arsenate, arsenite of zinc, Bordeaux mixture, arsenate of soda, and combination insecticides and fungicides. A little domestic white arsenic was exported, principally to Canada.

These incomplete reports account for all but 3,100 short tons of the available supply of white arsenic in 1923, and a considerable part of this remainder may have been consumed by the manufacturers who failed to report. At all events, any stocks of white arsenic held by manufacturers at the end of 1923 could have formed only a moderate margin over the quantity actually needed for current operations, and sales of arsenic compounds, with one exception, also nearly equaled the production. The demands for 1924 must therefore be supplied by new production.

Instability of the market, especially for calcium arsenate, continued to characterize the industry. Early in the year sales were retarded by contradictory information, some of it from apparently authentic sources, as is indicated by the following quotation: 10

The farmers were being charged too high a price, compared with the price of white arsenic; rumors of large supplies of low-priced calcium arsenate and at the same time of general shortage; wide range in price quotations; the availability of proprietary mixtures competing with calcium arsenate.

Under such conditions the farmers delayed or refrained from buying. Furthermore, the weevil season began about three weeks late. Speculators began to cancel contracts, as did others who had entered into ill-advised contracts. A little later the cotton-leaf caterpillar suddenly infested the cotton region, and there was a call for calcium arsenate at any price. It was this sudden demand that nearly exhausted what threatened to be an oversupply of calcium arsenate. Considerable quantities that had found no buyers were reshipped one or more times and finally consumed.

This reshipment was one of several factors in the spread in price between manufacturer and consumer. The average spread was 90

1 a Report of standing committee on arsenic, representing producers, manufacturers, and Government bureaus, Dec. 10, 1923.

per cent, and one or two shipments have been cited on which the spread was nearly 200 per cent. This unnecessarily high cost to the ultimate consumer will doubtless be reduced with the growth of the industry.

PRICES

The published prices of white arsenic quoted in New York City (see fig. 8) ranged from 152 cents a pound in January to 1134 cents in June and the last part of July. The lowest quotation of the year was 9 cents in August. Prices improved as the large consumers commenced to buy, and 15 cents a pound was bid in November. Red arsenic, which was all imported in 1923, was quoted at 13 to 16 cents a pound, but sales were made at 9 to 24 cents a pound. Metallic arsenic sold at 28 to 50 cents a pound. Sodium arsenite

FIGURE 8.-Quoted wholesale prices of white arsenic, 1920-1923. Figures for 1920-1922 from Chemical and Metallurgical Engineering, Dec. 20, 1922, p. 1241; for 1923 from Oil, Paint, and Drug Reporter, weekly quotations.

was quoted at $1 a gallon and sold at 55 to 70 cents a gallon. Lead arsenate, quoted at 18 to 24 cents a pound, sold for 17 to 24 cents; Paris green for 21 to 35 cents; and calcium arsenate, quoted at 12 to 19 cents, for 12 to 17 cents.

The actual sales of white arsenic ranged from 314 to 7 cents a pound, the bare cost of production, to 1114 cents, which most producers considered the lowest price at which they could afford to sell. There was no shortage of white arsenic at any time during 1923, but when prices began to rise those who had not already closed contracts with larger producers bought eagerly. This condition quickly increased the price for all odd lots in the hands of speculators. Current prices of white arsenic based on the prospective needs of the cotton planter have stimulated production for the increase necessary in the manufacture of calcium arsenate, but it is

a mistake to believe that there is a large quantity of arsenic readily available and that the price will revert to the former low levels. The cost of the smelter production of arsenic at the present time is higher as a result of the temporary exhaustion of the richer accumulated arsenical dust and the necessity for purchasing arsenic-bearing ores to increase the output. One writer in a recent publication,2 basing his argument on 5-cent arsenic, questions the advisability of "going to any great expense in the development of a mine solely for its arsenic content, or in the equipment of a new plant for the recovery of arsenic unless a good profit could be expected."

Manufacturers of white arsenic say that the cost of producing the refined product now averages about 7 cents a pound without allowance for overhead and depreciation, and there has been little incentive to domestic producers to sell at less than 1114 cents a pound. A drop in the market quotations for arsenic is naturally attributed to a temporary abundance of the imported product, but when this is exhausted the market is again in the hands of the American producer.

Freight charges on white arsenic from western points of manufacture to eastern consumers remained about the same in 1923 as in 1922. Some shippers had difficulty in procuring suitable barrels for white arsenic, to comply with the requirements of the transportation companies, but this defect was remedied.

ARSENICAL ORES

DEVELOPMENT

The reserves of arsenical ores in the Western States were considerably increased during 1923. The large deposit at Gold Hill, Utah, which is mainly scorodite (hydrous ferric arsenate), was developed below the 700-foot level and shown to be more extensive than previous reports had indicated. In the same vicinity another large deposit of arsenopyrite, oxidized to scorodite near the surface, was opened at a depth of 30 feet and followed to a depth of more than 100 feet. These ore reserves at Gold Hill will probably be the source of a large supply of arsenic for many years. The speiss dump at Eureka, Nev., from which 21,094 tons was shipped in 1923, was nearly exhausted at the end of the year, but to offset this loss several new arsenic deposits at Luning, Minden, Chafey, and Carson City were developed.

REVIEW BY STATES

UTAH

The largest immediate source of arsenic in Utah is opened in the old mining district of Clifton, near Gold Hill, Tooele County, about 9 miles east of the Nevada boundary. Most of the ore shipped in 1923 contained arsenic, which until the last two years has been valueless to the producer. Two of the three smelting companies having plants near Salt Lake City control the output from the two largest deposits in the district, but although interested in acquiring these

2 Eng. and Min. Jour.-Press, Aug. 11, 1923, p. 222.

properties they are not in the market for arsenical ores unless other metals are present. The freight rate to Salt Lake City from Gold Hill on strictly arsenical ores is $1.65 a ton, but if the ore has a greater value in other metallic constituents the rate is increased. Mining costs, which include loading the ore on cars at the Gold Hill mine, are said to amount to $5 a ton on a contract basis.

Prospecting for ore has not been active, on account of the cost of development and the small profit to the producer whose ores carry no gold, silver, copper, or lead. The district, however, is worthy of more prospecting for arsenical ore.

Butler, in a brief description of the geologic conditions, says:

The sedimentary rocks have been intruded by a body of quartz monzonite which has been exposed by erosion and occupies numerous areas amid the sedimentary rocks. Many of the smaller limestone bodies appear to be underlain at no great depth by monzonite and in fact appear to be sedimentary blocks resting on monzonite. The general arrangement of the sedimentary and intrusive rocks suggests that the present surface is near the more or less irregular top of an extensive body that occupies a large area in the district.

Near Gold Hill the limestone and shale form the eastern flank of the Deep Creek Range and locally reach altitudes of 1,000 to 1,500 feet above the desert plateau. The member of these sedimentary rocks of most interest to the miner is a massive limestone approximately 2,000 feet thick. Overlying the massive limestone is several hundred feet of impure sandy limestone and jasperoidal quartz, followed by about 2,000 feet of shale and sandstone. Mineralization has consisted in the replacement of the limestone at its contact with the quartz monzonite by deposits of silver-lead arsenic ore. The commercial part of the ore body, which is oxidized to the lowest levels, is a cellular mass of scorodite and brownish oxidized mineral (pharmocosiderite?), with small amounts of mimetite, cerusite, and monheimite. In the lower levels bismuth minerals have been found. Small residual masses of the primary ore consist of arsenopyrite and small quantities of galena, pyrite, sphalerite, and chalcopyrite, named in the order of their relative abundance, together with a little gold and silver.

In 1917 the production of ore was confined to the space between the 300-foot level and the outcrop and resulted in the output of 32,023 dry tons of ore. This ore averaged 0.013 ounce of gold and 4.71 ounces of silver to the ton, 2.67 per cent of copper, and 0.58 per cent of lead. The output in 1918 was 15,893 dry tons, containing 0.014 ounce of gold and 5.46 ounces of silver to the ton, 1.32 per cent of copper, and 3.34 per cent of lead.

The principal ore shoot and the only one exploited at the time of the senior writer's visit in 1923 is as a whole lenticular, with horizontal cross sections measuring between 7,000 and 8,000 square feet, but it varies greatly in shape on the different levels. The ore crops out in a very distinctive manner as a heavy brown to black iron gossan, exhibiting a marked contrast with the light-colored limestone. The ore shoot has been developed along its dip of 53° to a depth of 750 feet. The arsenic content of the ore appears constantly large from the 700-foot level to the surface except on the

Butler, B. S., Ore deposits of Utah: U. S. Geol. Survey Prof. Paper 111, p. 473, 1920.

400-foot level, where it is small and spotty. This body of ore measures on the 700-foot level 290 feet in length and averages about 60 feet in thickness, although it has been opened in one place for a horizontal distance of 90 feet. A raise from the 700-foot level was in ore for about 125 feet, and a winze from the same level was in ore at a depth of 50 feet, with indications good for the continuance of the ore for another 100 feet.

According to the record of the mining company, the average analysis of ore shipped from May to October in 1923, most of it mined above the 300-foot tunnel level, was 2.6 ounces of silver, 0.8 per cent of lead, 0.2 per cent of copper, 12.1 per cent of insoluble matter, 24.9 per cent of iron, 0.4 per cent of lime, 1.4 per cent of zinc, 1.4 per cent of sulphur, and 21.3 per cent of arsenic. The sampling of the ore on the 700-foot level gave a higher assay for silver, lead, and iron but less insoluble matter and less arsenic.

The foregoing description of the Gold Hill ore deposit is based on the senior writer's observations and on the reports of several engineers who examined the property during 1923. An average of the most moderate estimates of ore in reserve is 250,000 tons of 20 per cent arsenic ore, which includes ore on the deepest level.

The Last Dollar (Gerster) property, on the west slope of the ridge, about three-quarters of a mile south of Gold Hill post office, is developed by a 100-foot vertical shaft, with a short drift and crosscut driven northeast at the 90-foot level. The shaft was sunk by a lessee seeking scorodite ore. After passing through a greenish shaly deposit of scorodite, ranging in content from 2 to about 15 per cent of arsenic, it was continued in a body of massive arsenopyrite for 42 feet, to a depth of 72 feet, where the arsenopyrite changed to a mixture of arsenopyrite, galena, pyrite, and sphalerite in a quartz gangue. Below these sulphides scorodite of commercial grade and arsenopyrite continued to the bottom of the shaft and in the drift from the 90-foot level. Possibly 50,000 tons of 20 per cent arsenic ore was opened through this development at the end of 1923.

MONTANA

The Jardine mine, in the Sheepeater district, Park County, Mont., within 3 miles of the Yellowstone National Park, is an old one, and until the present company commenced operations, a few years ago, so-called free-milling ore was principally sought and the base ore containing arsenopyrite was neglected.

The ore deposits of the Jardine Mining Co. occur as lenses in mineralized shear zones in folded pre-Cambrian schist. These zones are approximately parallel to the schistosity and also to the original bedding. The general strike of the mineralized zones is north, but here and there they make rather abrupt turns, which conform to changes in the schistosity. The dips range from nearly horizontal to nearly vertical but in the principal stopes are mostly from 20° to 35° W., in general parallel to the slope of the mountain side.

The mineralizing solutions are believed to have ascended along certain permeable planes of schistosity. The deposits were formed largely by replacement of the soft schist, although there is also evi

Personal communication from H. C. Bacorn, Jardine, Mont.

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