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R.D. Crangle

Publications and source records attributed to R.D. Crangle.

8 recordsLinked to original sources

Diatomite

The United States continues to be the world’s leading producer and consumer of diatomite. Production of diatomite in the United States during 2012 was estimated to be 820 kt (903,000 st), a slight increase compared with 2011 production. The unit value of diatomite varied widely by end use in 2012. Diatomite used as a lightweight aggregate was priced at $11/t ($9.98/st), while specialty-grade diatomite, used in art supplies, cosmetics, or biomedical applications, could be priced as high as $10,000/t ($9,000/st). Filter-grade diatomite had an average unit value of $330/t ($299/st). Seven companies operated 10 mines and nine processing facilities in California, Nevada, Oregon and Washington. U.S. diatomite exports totaled about 96 kt (106,000 st). Imports were much lower at approximately 3.07 kt (3,380 st).

Mining Engineering

Borates

Four minerals represent 90 percent of the borates used by industry worldwide — the sodium borates (tincal and kernite), calcium borate (colemanite) and the sodium-calcium borate (ulexite). Borax is a white crystalline substance, chemically known as sodium tetraborate decahydrate, and is found naturally as the mineral tincal. Boric acid is a colorless crystalline solid sold in technical, national formulary and special quality grades as granules or powder and marketed most often as anhydrous boric acid. Deposits of borates are associated with volcanic activity and arid climates, with the largest economically viable deposits located in the Mojave Desert of the United States near Boron, CA, the Alpide belt in southern Asia and the Andean belt of South America.

Mining Engineering

Gypsum

The United States is the world’s fifth ranked producer and consumer of gypsum. Production of crude gypsum in the United States during 2012 was estimated to be 9.9 Mt (10.9 million st), an increase of 11 percent compared with 2011 production. The average price of mined crude gypsum was $7/t ($6.35/st). Synthetic gypsum production in 2012, most of which is generated as a flue-gas desulphurization product from coal-fired electric powerplants, was estimated to be 11.8 Mt (13 million st) and priced at approximately $1.50/t ($1.36/st). Forty-seven companies produced gypsum in the United States at 54 mines and plants in 34 states. U.S. gypsum exports totaled 408 kt (450,000 st). Imports were much higher at 3.2 Mt (3.5 million st).

Mining Engineering

Pumice and pumicite

Production of pumice in the United States during 2012 was estimated to be 515 kt (568,000 st), a 5-percent increase compared to 2011. The unit value of pumice varied widely by end use in 2012. Pumice used as an abrasive was priced at $10.30/t ($9.34/st), while specialty-grade pumice, used in cosmetics, filtration or precision grinding, could be priced as high as $400/t ($360/st) on a spot basis. Eleven companies operated 11 mines in Arizona, California, Idaho, Kansas, New Mexico and Oregon. U.S. pumice exports totaled about 12.5 kt (13,800 st). Imports were higher at 75.1 kt (828,000 st).

Mining Engineering

Gypsum

The United States is the world's fourth leading producer and consumer of gypsum. Production of gypsum in the U.S. during 2011 was estimated to be 9.4 Mt (103 million st), an increase of 6 percent compared with 2010 production. The average price of mined crude gypsum was $7/t ($6.35/st). Synthetic gypsum, most of which is generated as a fluegas desulfurization process from coal-fired electric powerplants, was priced at approximately $1.50/t (1.36/st). Forty-seven companies produced gypsum in the U.S. at 54 mines and plants in 34 states. U.S. gypsum exports totaled about 300 kt (330,000 st). Imports were much higher at approximately 3.3 Mt (3.6 million st).

Mining Engineering

Borates

Four minerals represent 90 percent of the borates used by industry worldwide — the sodium borates, tincal and kernite; the calcium borate, colemanite; and the sodium-calcium borate, ulexite.

Mining Engineering

Diatomite

The United States continues to be the world's leading producer and consumer of diatomite. Production of diatomite in the United States during 2010 was estimated to be 550 kt (606,000 st), a 4-percent decrease compared with 2009 production.

Mining Engineering

Pumice, pumicite review

The article focuses on the industrial mineral pumice. It mentions the estimated production of pumice in the U.S. in 2010, price range, and total U.S. exports and imports. Described as an igneous volcanic rock, pumice has low density which allows it float on water and porous enough to be used as building aggregate. Pumice may also function as an absorbent material, a filter aid, and a polishing agent among others.

Mining Engineering