GEOGRAPHICAL DISTRIBUTION OF SULPHUR
Italy and Sicily.
—Italy had practically a monopoly of the world’s sulphur supply until 1904, when large-scale production began in the United States. The importance of sulphur as a world mineral began with the use of gunpowder in the fourteenth century. Considerable export trade was early developed and has been of increasing importance since 1830. Ninety per cent. of the Italian production has come from the Island of Sicily.
The sulphur-bearing district of Sicily is a central belt running across the island, extending about 100 miles east and west and 50 miles north and south. The richer deposits are scattered as irregular lenses or basin-like bodies, in this extensive area. The deposits of commercial value are of sedimentary type, occurring as stratified beds or sheets in limestone, associated with gypsum and bituminous marl. There are generally three or four sulphur-bearing layers, separated by a few feet of barren rock. The average thickness of the sulphur beds is from 10 to 15 feet, although in a few places they run as high as several hundred feet. The sulphur occurs as incrustations, pockets, or thin bands intimately associated with the limestone. The average sulphur content of the ore mined is from 20 to 25 per cent., with a range from 8 to 50 per cent.; and in a few places it reaches up to 90 per cent. Estimates as to the reserves of ore vary greatly, but seem to indicate that there is from 40 to 60 million tons of ore still unmined, which will average about 23 per cent. of sulphur content.
Mining has been mostly by hand and the ore brought out on the backs of men. A few mines had modern hoisting machinery and trams. The shortage of labor during the war has increased the introduction of modern appliances in some of the newer mines. With increasing depth the cost of mining has increased to the point where American sulphur can compete in European markets.
The methods of extracting the sulphur from the ore have also been extremely crude and wasteful, but in the last few years better types of ovens have been installed, giving a much higher recovery through improved distillation and the use of superheated steam for melting the sulphur.
The sulphur industry of Sicily furnishes a notable example of an attempted commercial control which developed into a governmental control of the industry. The recent history of the industry falls into three periods. The first extends from 1875 to 1895 and is characterized by a rapid increase in production, from 200,000 to 400,000 tons a year, with a corresponding decrease in selling price from $25 a ton to as low as $12 a ton. It was a period of overproduction, due to the ease with which shallow mining could be carried on and to the abundant supply of cheap labor available. These conditions resulted in the development of a great number of small mines, whose competition reduced prices. The second period, from 1896 to 1906, begins with the formation of the Anglo-Sicilian Sulphur Co., financed by English capital, which entered into a five-year agreement with the principal producers, which was later extended for an additional five years. It was primarily a marketing organization, formed by the union of Italian and English interests to control production, stabilize the industry, and maintain prices. It eventually controlled from 75 to 85 per cent. of the industry. All sulphur was purchased at about $16 per ton f.o.b. ship and the selling price remained practically stable during the ten-year period, at an average of $18 to $19 per ton. In spite of efforts to restrict production, the annual output reached 550,000 tons during most of this period. At the same time the higher prices maintained for sulphur had stimulated the use of pyrite as a substitute. In order to maintain prices under these conditions the excess production had to be purchased and stored, so that in 1906 a stock of over 500,000 tons of sulphur had been accumulated in Sicily. Toward the end of this period large-scale production began in the United States (1904). In 1903 the United States produced less than 10,000 tons of sulphur and was Italy’s best customer, buying over 170,000 tons in that year. Within three years the United States was producing more than enough to supply its own needs and was accumulating a large reserve stock. The sudden loss of the American market and the threat of competition in other markets brought on a crisis in the Sicilian industry, which was intensified by the large number (30,000) of people employed in the industry. At the termination of the agreement with the Anglo-Sicilian company (July 31, 1906) steps were taken by the Italian government to control the situation. The third period, from 1906 to the present, is one of government intervention and control of the industry. All the producers were compelled to join a company called the “Consorzia Obbligatoria per l’Industria Solfiefera Siciliana,” organized under a law passed in the Italian Parliament. The organization was managed by a commission appointed by the government, and had complete control over exports and prices. All sulphur had to be sold at fixed price to this organization. A minimum interest was guaranteed on the capital invested; local freight rates on sulphur for export were reduced; sulphur stocks accumulated by the Anglo-Sicilian company were taken over; and a campaign of price-cutting was started in the American market, which resulted in a decrease of several dollars a ton in the selling price of sulphur. A market agreement was soon reached and prices recovered. A number of the smaller mines closed down and a law was passed controlling and restricting the granting of new concessions. Production declined to 350,000 tons in 1913. At the opening of the war the principal United States producer was preparing to enter into more active competition with Italian sulphur, particularly in the French markets. As a result of the war, Italian production dropped to only 180,000 tons in 1917, largely due to labor shortage; about half of the surplus stocks were used up, leaving only 160,000 tons on hand at the end of 1917; and prices increased so that refined sulphur sold at about $80 per ton and inferior grades at $55 per ton, f.o.b. Sicilian ports. The increasing cost of producing sulphur, due to deeper mining and increased labor costs, will make it difficult to compete in the European markets with the greatly expanded production of the cheaper American article.
Sulphur has been produced in several districts in the Italian peninsula, particularly Romagna, Marches, Campania and Calabria. The yield from these districts has been decreasing in recent years and has generally been only from 25,000 to 30,000 tons. The sulphur content of the ores ranges from 20 to 30 per cent. The deposits are of limited extent and are being mined at greater depths. The production has been largely used for local agricultural purposes, in preparations for use against vine diseases.
The United States.
—Until 1904, the production of sulphur in the United States was considerably less than 10,000 tons per year and the bulk of our requirements had to be met by import from Sicily. From 1904 to 1914 the United States produced enough for its own use and at the end of this period was supplying Canada, had begun to actively enter the French and German market, and in addition had accumulated a reserve stock, in the hands of the producers, of approximately one million long tons. Figures recently made public in connection with litigation over patent rights show that half of this stock was accumulated in a single year, 1912, when production reached 790,000 long tons, of which only 300,000 tons was marketed and the balance of 490,000 tons went into storage. The United States production has exceeded that of Italy since 1912, although the sales have been less, because sulphur was being withdrawn from stocks in Italy while stocks in the United States were being increased. The net effect of the war was a four-fold increase in the amount of sulphur sold in the United States, without any reduction in stocks; while in Italy production fell off 50 per cent. and stocks on hand were reduced by the same percentage.
From 98 to 99 per cent. of the United States production has come from the Gulf Coast region of the states of Louisiana and Texas. A number of other localities in West Texas, Colorado, Wyoming, Idaho, and Nevada have surface deposits, usually of limited extent, which have been worked on a small scale, but have declined in importance with the development of the better-grade and more accessible deposits of the Gulf Coastal region.
The occurrence of sulphur in the Gulf Coast region is in connection with a peculiar formation known as “Saline Domes” or “Mounds.” Over twenty of these domes have been located, scattered in an area 200 miles long, extending through western Louisiana and eastern Texas, and generally within 50 miles of the Gulf of Mexico. Commercial deposits of petroleum, sulphur, and salt have been developed in connection with these domes, but so far not more than one of the minerals has been developed to commercial degree in a single dome. Sulphur was discovered when drilling was being carried on for oil. So far, three domes have been developed for sulphur, namely that owned by the Union Sulphur Co. at Sulphur, La. (1903), that owned by the Freeport Sulphur Co. at Freeport, Texas (1912), and that of the Texas-Gulf Sulphur Co. near Matagordo, Texas (1919). Two other domes are under exploration and a number of others may possibly contain sulphur.
The sulphur occurs at a depth of 300 to 1,200 feet and is associated with limestone and underlain by gypsum. The surface area of the producing domes varies from 200 to 1,500 acres. Exploration is done by drilling at a cost of $200,000 to $300,000, and the cost of a complete plant is several million dollars. The sulphur cannot be mined by shafts, due to the quicksands and the poisonous gases encountered. The deposit at Sulphur, Louisiana, remained unworked for almost 40 years after its discovery before a satisfactory process was developed to mine it. This is known as the “Frasch Process” and consists of the sinking of wells to the sulphur deposit, each well being lined with a 10 to 12 in. pipe. Smaller pipes are placed inside, so that superheated water can be brought in contact with the sulphur ore, which is melted and forced to the surface by compressed air. The sulphur on cooling is ready for market and is over 99 per cent. pure. Each of the three plants in operation is equipped with a boiler capacity of over 20,000 h.p. for superheating the water, and requires about a million and a quarter barrels of fuel oil per year. The origin of these domes is believed to be due to deep-seated igneous intrusions, resulting in the alteration of gypsum and the crystallization of salt and sulphur, which has caused an upbowing of the strata. Because of the nature of the formation and the irregularity of the deposits it is impossible to accurately estimate the reserves of sulphur.
With the addition of two new plants since 1912, the United States now has a sulphur-producing capacity of about 1¹⁄₄ million tons per year, or four times the normal sales before the war. If an outlet is to be found for this excess sulphur, it must compete with pyrite in the domestic market or with Sicilian sulphur in the European markets. In the latter part of 1919 prices of $14 to $15 per ton f.o.b. mines were quoted, which indicated that an effort was being made to secure part of the acid trade which formerly used pyrite.
There is no element of political control in the United States sulphur industry, beyond the temporary measures taken during the war in licensing export and allocation of consumption. The commercial control is entirely in the hands of American companies. The Union Sulphur Co. has been endeavoring to prevent the use of the improved “Frasch Process” by the other companies which are competing with it. If the claim of infringement of patent rights should be sustained, it would give the Union company control of the situation similar to that which it had before the development of the two newer companies, and might result in the restriction of output and maintenance of prices.
Japan.
—Japan takes third rank in the production of sulphur, although it is of minor importance, compared to either the United States or Italy. The production of sulphur in Japan has slowly increased from 15,000 long tons in 1900 to 60,000 tons in 1913, or about 7 per cent. of the world output. The domestic consumption is very small and about 90 per cent. of the output was exported, chiefly to Australia, the west coast of the United States and Canada, and to China and India. During the war the output increased to a maximum of about 100,000 tons, but in 1918 production was considerably curtailed by the great advance in freight rates to Australia, which had been purchasing about one-half of the Japanese output.
The sulphur occurs in surface deposits of limited extent and seldom reaches 100 feet in thickness. The deposits are generally of the solfataric type and occur in the numerous areas of volcanic activity. The majority of the productive areas are nearly circular in outline, and indicate that they were formed by deposition in crater lakes. In some cases they are stratified and overlain by fine brown clayey or tufaceous material derived partly from the surrounding rocks and partly from the sulphur itself. Other deposits of minor importance may have been produced by impregnation. The ore mined runs from 50 to 60 per cent. sulphur. Deposits below 40 per cent. sulphur are seldom worked.
Approximately two-thirds of the production has come from the southwestern section of the Island of Hokkaido. Four mines average about 10,000 tons production each per year, and the remainder of the production comes from 10 to 12 smaller operations, ranging from the vicinity of Mount Daiton, in Taiwan (Formosa), to the Kurile Islands.
There is no accurate estimate of ore reserves available. One of the most important mines was estimated as containing several million tons of 50 per cent. ore. The reserves are probably sufficient to maintain present production for many years. The lack of shipping facilities has handicapped production, and there seems little likelihood that the relative importance of Japan in the sulphur industry will increase to any great extent.
The sulphur mines are all operated by Japanese. The state reserves the right of original ownership of all minerals, except a few placer deposits. Right of working is granted to Japanese companies or individuals according to priority of application. The mining law, however, acknowledges the rights of any corporation organized by aliens under Japanese law.
Great Britain.
—Great Britain has an estimated annual by-product recovery of from 30,000 to 40,000 tons of elemental sulphur. The process of recovery is known as the Chance-Claus process, and is applied in connection with the Le Blanc soda process. It is based upon the decomposition of calcium sulphate in vat waste by means of carbon dioxide, and the recovery of sulphur from the sulphuretted hydrogen gas thus generated.
Other Countries.
—The production of sulphur outside of the United States, Italy and Japan is of minor importance.
Northern Chile has a small production of sulphur from the volcanoes of Tacora and Chupiquina. The reserves are estimated as quite large, but the high elevation (14,000 to 20,000 ft.) and poor transportation have restricted production to local uses in the vineyard districts of Chile. The production as reported had gradually increased to about 6,000 tons in 1913 and is reported to have doubled since then.
Spain produces about 10,000 tons of sulphur annually, from low-grade deposits located in the neighborhood of Almeria. The larger figures often reported are in terms of low-grade ore mined.
Austria is credited with a production of from 10 to 15 thousand tons of crude sulphur ore, probably representing only 2 or 3 thousand tons of actual sulphur.
The largest sulphur mine in Mexico is located at Cerritos, 25 miles south of Guadalcazar, San Luis Potosi. Fifteen years ago it was purchased by an American company, the Virginia-Carolina Chemical Co. It was later leased to German interests. The small output of a few thousand tons was shipped to Germany before the war. There are a number of deposits in San Luis Potosi in addition to the one at Cerritos.
It has been reported several times that a British company was about to operate the sulphur deposits of the Mexican volcano, Popocatepetl, near Mexico City. Statements regarding the deposits in the volcano are conflicting, but investigations indicate that their magnitude has been much exaggerated. Many other deposits occur in connection with local volcanic areas, but so far are of little economic value because of inaccessibility.
There are a number of deposits of sulphur in the Aleutian Islands (Alaska), probably containing considerable sulphur, but partially covered by glaciers and difficult of access. It is doubtful whether they could be developed in the face of the competition of the cheap sulphur from the coastal plain district of the United States.