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W.P. Bolen

Publications and source records attributed to W.P. Bolen.

7 recordsLinked to original sources

Perlite

Domestic production and prices of crude processed perlite in the United States were estimated to have increased in 2012 compared with 2011. Perlite trade, both imports and exports, slowed in 2012 compared with 2011. With imports of perlite down by about 13 percent and domestic production up slightly, the balance resulted in a consumption decrease of about 20 kt (22,000 st). The estimated amount of processed perlite sold or used from U.S. mines in 2012 rose to 424 kt (467,000 st) from the upwardly revised total of 420 kt (463,000 st) sold or used in 2011. U.S. consumption of crude processed perlite increased in 2010 and 2011, but 2012 consumption was estimated to have decreased by about 3 percent to 557 kt (614,000 st). However, these 2012 estimates are still 19 percent higher than the consumption of 2009, when only 468 kt (516,000 st) of perlite was consumed (Table 1). Significantly increased U.S. construction activity during late 2012 likely indicates increased consumption of building materials, the leading market for perlite.

Mining Engineering

Perlite

Domestic production, consumption, exports and imports of perlite in the United States were estimated to have increased in 2010, compared with 2009. Even so, they were still considerably below the running five-year averages.

Mining Engineering

Perlite

Consumption, imports and domestic production of perlite in the United States continued to be severely affected by the multi-year downturn in construction activity and decreased consumer spending. The estimated amount of processed perlite sold or used from U.S. mines in 2009 fell to 380 kt (418,000 st), the lowest amount of domestic perlite sold or used since 1967.The U.S. consumption of crude processed perlite in 2009 was estimated to have decreased to 480 kt (530,000 st), the lowest level of consumption since 1984 when consumption was 474 kt (522,000 st). Preliminary reports indicate that perlite imports decreased for the third consecutive year and have fallen about 45 percent since peaking in 2006.

Mining Engineering

Construction aggregates

Construction aggregates, primarily stone, sand and gravel, are recovered from widespread naturally occurring mineral deposits and processed for use primarily in the construction industry. They are mined, crushed, sorted by size and sold loose or combined with portland cement or asphaltic cement to make concrete products to build roads, houses, buildings, and other structures. Much smaller quantities are used in agriculture, cement manufacture, chemical and metallurgical processes, glass production and many other products.

Mining Engineering

Pumice and pumicite

The estimated domestic production of pumice and pumicite in 2002 was 950 kt (1.04 million st), a 3.2 percent increase compared with the revised total of 2001, according to the U.S. Geological Survey (USGS). The amount of pumice and pumicite sold or used in the United States was revised for the years 1998 through 2001 in the USGS Mineral Commodity Summaries, 2003.

Mining Engineering

Construction aggregates

The estimated production during 2000 of construction aggregates, crushed stone, and construction sand and gravel increased by about 2.6% to 2.7 Gt (3 billion st), compared with 1999. The expansion that started in 1992 continued with record production levels for the ninth consecutive year. By commodity, construction sand and gravel production increased by 4.5% to 1.16 Gt (1.28 billion st), while crushed stone production increased by 1.3% to 1.56 Gt (1.72 billion st).

Mining Engineering

Construction aggregates

Construction aggregates consist primarily of crushed stone and construction sand and gravel. Total estimated production of construction aggregates increased in 1999 by about 2% to 2.39 Gt (2.64 billion st) compared with 1998. This record production level continued an expansion that began in 1992. By commodities, crushed stone production increased 3.3%, while sand and gravel production increased by about 0.5%.

Mining Engineering