MINERAL PRODUCTS. 
33 
worked since 1845. The barite deposits of Bedford, Campbell, and 
Pittsylvania counties, in the south-central part of the State, cen 
tered about Evington and Toshes, are in highly altered crystalline 
rocks formed from old sedimentary and igneous rocks. Barite has 
been found associated with similar rocks in six other counties in the 
Piedmont region, but has not been mined to any considerable extent. 
In southwestern Virginia, in Tazewell, Wythe, Bussell, and Smyth 
counties, barite occurs in the Cambrian and Ordovisian limestones 
or their residual clay. 
Deposits of barytes are known in Mariposa County, in California ; 
in Clark, Elko, Mineral, and Nye counties, in Nevada; in Blaine 
County, in Idaho ; and in Alaska. Most of the deposits in the West 
ern States are undeveloped, as there has apparently been a scanty 
market for this material ill that region, and railroad freight rates 
have not permitted western barite to compete with either foreign or 
domestic barite in the principal centers of use in the East. In 1913 
E. F. Burchard, of the United States Geological Survey, discovered 
a considerable deposit of barite associated with quartzite schists on 
Castle Island, in the Duncan Canal, 40 miles northwest of Wrangell, 
in Southeastern Alaska. 
Witherite, or barium carbonate (BaCO ;i ), is used in the manufac 
ture of glass and porcelain, and in the preparation of oxygen, barium 
salts, boiler compounds, vermin poisons, and green fire. It is a 
dense, soft white powder, which is poisonous. So far as is known 
to the United States Geological Survey, there are no deposits of 
witherite of commercial size in the United States. Commercial 
deposits have been mined in England, Silesia, Hungary, Styria, and 
Russia. Barium carbonate can be prepared by igniting a mixture of 
10 parts of powdered barite, 2 parts of charcoal, and 5 parts of 
potassium carbonate. Potassium sulphide and barium carbonate 
result from the reaction, and may be separated by water, as barium 
carbonate is very sparingly soluble in water. Another method of 
preparing barium carbonate is by heating 100 parts of powdered 
barium sulphate with 250 parts of sodium carbonate and 200 parts 
of water in autoclaves at 5 atmospheres pressure. 
phosphate rock. 
Of the mineral fertilizers phosphate is the one of which the United 
States has large reserves. The fields and gardens of Europe largely 
depend on this supply, nearly one-half of our production going to 
trails-Atlantic ports. The great bulk of the phosphate rock exported 
is obtained in Florida and, of course, includes chiefly the better 
grades. 
Though phosphate rock is an important item of export, interrup 
tion of the foreign sales can not be regarded as a national calamity. 
59170°—Bull. 599—14 3