render it unfit for this special use. The price of Sicilian per ton of 2,240 pounds at the close of 1882 was $27.50 for best unmixed seconds, and $26 for best thirds. The price fluctuates considerably, and has declined from the rates ruling earlier in 1882.

The following tables show the extent of the foreign trade during recent years:

Crude sulphur or brimstone imported into the United States during the fiscal years specified. (Specie values.)

Refined sulphur imported into the United States during the fiscal years specified. (Specie

values.)

Sulphur exported from the United States during the fiscal years specified.

BARYTES.

Productive localities.-The leading producing localities in the United States are in the States of Virginia, East Tennessee, Missouri, Connecticut, and North Carolina. Illinois, Kentucky, Maine, and Pennsylvania also produce barytes. It was formerly mined in New York, but the industry has latterly declined, as the cost of mining was too high to meet competition. The mineral commonly known as "heavy spar." "barytes," and sometimes as "baryta," is the barium sulphate (barite). Carbonate of barium (witherite, bromlite) is not mined in this country.

Mode of manufacture.-Messrs. Page & Krause, of Saint Louis, who own important mines near the Osage river, Miller county, Missouri, report their process of manufacture as follows: (1) sorting the ores; (2) refining with sulphuric acid; (3) "floating" the refined product; (4) packing. The Marion Barytes Works, Smyth county, Virginia, produced 2,000 net tons in 1882. The mineral is here prepared for market by (1) separating from it the gray limestone and ferruginous inpurities; then (2) washing and scouring in revolving cylinders; (3) hand-sorting and grading; (4) grinding in buhr mills; (5) "air-floating," and finally (6) packing in barrels. The picking and sorting are performed by boys, of whom 50 are employed. The spot value of the crude barytes in this locality is, averaging all grades, about $12 per ton of 2,000 pounds.

The business of grinding barytes is an extensive one. German stone is imported and powdered here. Messrs. Burgess & Newton, of New Haven, Connecticut, report grinding 4,000 tons of German barytes in

1882.

Production. The following table shows the production of ground barytes in the census year 1880. It includes, however, the foreign stone which was treated in this country:

Production of ground barytes during the census year 1880.

The production of crude mineral in the United States in 1882 is estimated by Messrs. Page & Krause at 20,000 tons, and that of Missouri

alone at 8,000 tons; and it is stated that the production could be largely increased to meet an augmented demand. The mine owned by Messrs. Davis & Hewitt, near Irvington Station, Campbell county, Virginia, reports a capacity of from 100 to 200 tons per day, and other mines also could produce more largely than at present. It is difficult to fix the average spot value for the crude mineral. Ground barytes in 1882 averaged about $22 per ton, and the value of the crude may roughly be placed at $8 per ton, at the point of manufacture, making a total value for the crude mineral of $160,000.

Utilization.-Barytes is used very extensively in the arts, but almost altogether for purposes of adulteration, for which its leading use (about 90 per cent.) is in replacing to a greater or less extent white lead in paint. One firm claims that a mixture of one-third white lead, onethird oxide of zinc, and one-third "floated" barytes makes a better paint than pure white lead. Paint works, however, do not generally advertise the fact that their product contains barytes, although this is, of course, well understood in the wholesale trade. It is also employed as a "filling" for general purposes, in pulp, and in making putty.

Tariff-The duty under the new tariff on crude barytes is 10 per centum ad valorem, and on manufactured barytes one-fourth of 1 cent per pound. Of the imported carbonate 75 per cent. is used in the paint trade, and the remainder chiefly in pottery making.

STRONTIA.

Occurrences.-The strontia minerals have been identified at many points in the United States, and probably occur more frequently than is generally supposed, as systematic search for them has not been prosecuted to any extent. Strontianite (strontium carbonate) has been found at Schoharie, New York, in hydraulic limestone; at Muscalonge lake, New York; at Chaumont bay and Theresa, Jefferson county, New York; and in Mifflin county, Pennsylvania. Celestite or celestine (strontium sulphate) occurs at Green or Strontian island and North Bass island, Lake Erie, where it occurs in magnesian limestone of the Water-lime group, at the former locality being found in large masses of beautiful crystals; and at Chaumont Bay, Schoharie, Lockport, the Rossie lead mines, Depauville, and Stark, in the State of New York, and also at Bell's Mills, Blair county, Pennsylvania. The blue fibrous variety found in Pennsylvania is the celestite originally taken to Europe by Schütz and named by Werner.

Small lots of American strontia have been offered in the market from time to time, but have not met with a ready sale.

Uses.-Nitrate of strontia is used in this country to a considerable extent by the makers of fireworks. It is made here by the chemical manufacturing works from imported carbonate. An increased demand has recently sprung up in Europe, owing to the introduction of a new and successful process for treating beet sugar, which promises to absorb large quantities of strontia in comparison with the former consumption. Strontia has also been recently utilized in the manufacture of tuyeres for blast furnaces. These new applications will undoubtedly lead to active prospecting for and mining of strontia minerals, and will tend to develop localities which heretofore have not been productive.

The amount of celestine mined in Sicily, the principal source of this mineral, is reported to have been about 4,000 gross tons in 1881.

582

MICA.

Occurrences.-Muscovite mica, varying greatly in quality and the size of sheets, occurs in nearly all of the granitic, gneissoid, and schistose areas of the country. At present North Carolina takes the lead in point of production. In that State, since 1868, mica has been mined in many places, and has been obtained in plates sometimes over 3 feet in diameter. Numerous localities exist in Macon, Jackson, Haywood, Buncombe, Ashe, McDowell, Yancey, Alexander, Cleveland, and other counties. Merchantable mica is also found in many other of the South Atlantic States. A considerable amount is mined in Maine and New Hampshire. A recent discovery, said to be important, is announced to have been made in Salisbury township, Pennsylvania. At South mountain, in the same State, a new mine has been opened, which is said to have produced pieces of good mica weighing from 19 to 27 pounds, some of which could be split 160 times to the inch.

Mica is found in numerous States and Territories contiguous to the Rocky mountains. In a few localities it occurs in medium-sized plates of good quality; but in this region only the mines of Deadwood, Dakota, and one mine near Las Vegas, New Mexico, have shipped any mica to market. The McMaken mine, near Deadwood, had sold up to May 140,000 pounds of merchantable mica, and the Sundog, Black Hills, and other mines have shipped small quantities. The mica from these mines is of excellent quality, and plates are sometimes produced 12x18 inches in size. The main ledge is said to be 14 feet wide, and to consist of a central mass of feldspar and "porphyry," with a casing of mica, which varies in width from 3 to 4 feet, on each side. The country rock is granite. These mines have hitherto been developed only by open cuts, and until recently have never been steadily worked.

In Wyoming mica occurs occasionally in plates 4x6 inches in size, and of good quality; but the supply is extremely limited. In Colorado good plates of mica have been found in Boulder, Jefferson, and Fremont counties, but only in very small quantities. In New Mexico, near Las Vegas, it is said to occur in considerable amount, some of the plates being 8x14 inches; but although found in large quantity only a few small pockets produce sheets of marketable size. One small shipment has been made.

Mica of excellent quality has also been discovered on the Payette river and in other localities in Idaho. Local excitements about mica. claims are frequent in Nevada; but thus far there has been no actual