production. A number of claims were located in the southern portion of Nye county during the past winter.

Deposits of mica are found in nearly every county in California, and in many of the mining districts and at various other points on the Pacific coast. As a general thing, however, it is of somewhat inferior quality, though some quite clear and in large sheets has been discovered. No regular mica mining is done in this portion of the country, though several deposits have been opened with the hope that systematic developments would ultimately be made. Still, the local market is quite limited, and there has been no encouragement for miners to open the deposits they have found.

Prospectors in search for gold and silver in Alaska report that deposits of mica are numerous in that Territory.

Production. The total production in 1882 is estimated by Messrs. Munson, Rolls & Co. at 75,000 pounds of sheet mica, with a total value of $250,000, which would give an average of $3.33 per pound. There is little doubt that the product will be largely augmented by the recent important discoveries, especially those in the Black Hills region.

Uses.-The clear, transparent, and tough mica plates are used in various ways, the principal utilization being for stove and furnace doors. A small amount of specially fine mica is used for compass plates. Mica generally occurs in plumose or scaly forms, rendering it valueless for its best known uses. These varieties are pulverized and used as an absorbent in one variety of nitro-glycerine explosives, and enter also into a patented lubricating composition for axles and bearings. Ground mica is also employed for various ornamental purposes. Scrap mica and trimmings from the better kinds are pulverized and utilized in the same way as the inferior varieties. The demand for ground mica, however, is comparatively small, and the supply of mineral suitable for the purposes to which ground mica is applied is abundant.

Value. The price ranges from 25 cents to $5 per pound, according to the size of sheets and quality. Some exceptionally large and clear sheets from North Carolina have been sold at $10 per pound; but mica of this grade rarely comes on the market.

TALC.

Occurrences.-Talc is mined in many States on the Atlantic seaboard, and is known to occur in many scattered localities of the West. Pennsylvania is a principal producing center. A bed has recently been opened in Georgia which produces an article that by samples is said to be much superior to the imported tale. When this mine is reached by a railroad now being built, it is expected to make a large output.

Production.-No reliable statistics were obtained as to the product of this mineral in 1882. Some dealers estimated it as high as 50,000 net tons; but probably half that amount would more than cover the actual output. The average spot value is about $12 per ton. The imported talc, of which $20,960 worth was received in the fiscal year 1882, is of generally superior quality, and the average price is about $22 per ton. Our importations come from Italy, Austria, and France.

Uses.-Talc is used extensively in soap-making, and also for dressing fine sheep-skins, leather, gloves, etc. The domestic tale is used in the manufacture of paper, replacing terra alba for this purpose. A small amount of talc enters into the composition of some lubricating compounds

585

QUARTZ.

Various uses are made of quartz in the arts. Fine rock quartz is used extensively in glass and pottery making, and as a grinding and polishing powder. It is estimated that above 75,000 tons are annually consumed in the United States for these purposes. A considerable quantity of fine quartz sand is used for glass-making, and is included in the foregoing estimate. Ground quartz, especially of the flinty variety, as well as powdered glass, are used extensively in the manufacture of sandpaper. Twenty-seven thousand two hundred and eighty-seven dollars' worth of quartz sand was imported in the fiscal year 1882. There is also a small importation of" flint stone." Our exports of quartz are insignificant.

586

FLUORSPAR.

Fluorspar is found in more or less quantity in almost every State and Territory, but not very frequently in workable amount. No statistics of production are accessible, and the estimates of dealers vary widely; but the amount annually mined is very considerable, possibly reaching 5,000 net tons per annum. Fluorspar is used as a flux and as a glaze in the pottery trade, and in the production of hydrofluoric acid for etching. The greater part consumed in this country is from home sources, little now being imported; and the domestic mineral is reported to be superior. Its spot value ranges from $10 to $20 per ton. Indiana and Ohio are said to lead in point of production. New York, Delaware, New Hampshire, and Kentucky also contain fluorspar in noteworthy

amount.

Fluorspar in the Rocky Mountain region.-Fluorspar occurs massive in wide metalliferous veins near Bear creek, in Jefferson county, and on James creek, Boulder county, Colorado. The white, green, pink, and purple colors are common, and often all these colors occur in a single specimen. The mines at Bear creek have produced some 600 tons of fluorspar, which was sold to the Boston and Colorado Smelting Works at Black Hawk before they were removed to Argo. The supply from this point is exhausted. On James creek the veins of fluorspar are undeveloped, as there is no demand for it as a flux. Fluorspar occurs frequently in the ores of Montana, Wyoming, Colorado, and New Mexico, but only in small quantities. It is used as a flux in local smelting operations, but is not much in demand. Fine cabinet specimens come from Crystal Park, El Paso county, some showing crystals 10 inches

across.

587

ASBESTUS.

Occurrences.-Asbestus is found, usually in small quantities, in very many localities in this country. The great difficulty connected with the economical mining of this substance has been that the deposits are gen. erally small pockets. Both hornblende and pyroxene asbestus occur, the former being the more common, though it is often difficult to distinguish between these varieties. Most of the bisilicates, excepting those containing much alumina, pass into fibrous varieties, all of which are known as asbestus, though the term "amianthus" is sometimes applied to the finer and more silky kinds. The leading localities at which asbestus is or has been mined are Rabun and Fulton counties, Georgia; also localities in northern Georgia, western North and South Carolina, Staten Island, Long Island, and other localities in New York State, Maryland, northern New Jersey, Pennsylvania, and Virginia. Small quantities of good quality have also reached the market from Colorado, and the occurrence of the mineral is noted in many of the Territories.

There are very many places in California and Nevada where asbestine deposits are found. In San Bernardino county, near Agua Caliente, San Diego county; Salt Spring valley, Calaveras county; Placer county, and at several other points in California deposits have been opened. While the mineral in some of these localities occurs in great masses and is remarkable for its length of fiber, it has generally been lacking in fineness, flexibility, or other desirable properties. For these and other reasons, such as the cost of mining and transportation and the limited local demand, the home product has not been able to compete with imported and Eastern asbestus in the San Francisco market, notwithstanding its lower price, that of the raw material varying from $30 to $35 per ton. Deposits of the different varieties of the mineral have been found at a number of other places in the Pacific States and Territories, but so few of them have ever been developed that in regard to their value or character little is known. Asbestus seems to be abundant enough in this region, but it is difficult to find it in such a form as to be acceptable to the purchasers.

Production, etc.-The production in the calendar year 1882 is esti mated at 1,200 tons, of an average spot value at the mines of $30 per ton. It is expected that larger quantities will be mined in the future, and that the product can be put upon the market at a lower cost. The price at New York reaches from $15 to $60 per ton, according to purity and length and strength of fiber. The imports of crude asbestus dur