- Searles Lake
Searles Lake (also called Searles Dry Lake), is an evaporite basin located near the community of Trona in
San Bernardino County ,California . Searles Valley Minerals currently extracts 1.7 million tons of industrial minerals each year from several lakebeds within the basin.Geology
Searles Lake is one of a chain of
Pleistocene lakes that extends fromOwens Lake to as far as ancientLake Manly inDeath Valley . The stratigraphic record at Searles Lake indicates that it once held brackish water as deep as 200 meters (650 feet). Fluctuations in lake levels correspond to the advances and retreats of glaciers in the Sierra Nevada Range. Thirty major lake levels occurred during the last 150,000 years, represented by a sequence of salt and mud beds. The precipitation of minerals occurred during long periods of lake evaporation.The lake is home to theTrona Pinnacles , a spectacular geologic tufa formation and aNational Natural Landmark .History
Borax was first produced from the dry lake surface in1873 by John Searles under the name of the San BernardinoBorax Mining Company . Searles was the first to haul borax using the famous20 mule team wagons. In 1873, before the railroad was built to Mojave, refined borax was hauled 175 miles by 20 mule teams fromSlate Range Playa (now called Searles Lake) to the harbor at San Pedro. The Searles Lake borax discovery has been designated asCalifornia Historical Landmark #774, with a plaque at the roadside rest area in Trona. [http://ohp.parks.ca.gov/default.asp?page_id=21476]Mineralogy
Searles Lake is a huge resource of
sodium andpotassium minerals of thecarbonate ,sulfate ,borate andhalide classes of mineralogy. The manufacture of industrial minerals involves a complex solution mining operation in which naturally occurring brines are pumped from wells completed in several salt beds. The brine wells range in depth from near-surface to over 100 meters below the salt pan. A network of production wells, injection wells, solar ponds and piping are used in the production and treatment of the brines.Industrial minerals are extracted from the brines at the Argus, Trona and Westend plants. Minerals are crystallized from the brines, screened, washed, and dried. The crystals are then baked in rotary kilns in order to drive off water molecules locked in the crystalline structure. Some recrystallization may be required in order to achieve a desired composition and granular density. This complex extraction process at the 3 plants is generally referred to as fractional crystallization. It includes the treatment of brines through carbonation extraction, refrigeration extraction and/or solvent extraction. Salt is also harvested from the lake surface and from solar ponds with use of heavy equipment.
Commodities produced by Searles Valley Minerals from their Searles Lake operations include
borax ,V-Bor (borax with 5 moles of water),anhydrous borax ,boric acid ,soda ash ,salt cake andsalt . Mineral reserves exceed 4 billion tons.Mineral List
*
Analcime
*Aphthitalite
*Borax
*Burkeite
*Galeite
*Gaylussite
*Gypsum var:Selenite
*Halite
*Hanksite
*Heulandite
*Feldspar
*Merlinoite
*Mirabilite
*Nahcolite
*Northupite
*Opal
*Phillipsite
*Pirssonite
*Schairerite
*Searlesite
*Sulphohalite
*Teepleite
*Thenardite
*Tincalconite
*Trona
*Tychite
*Ulexite References and external links
* [http://www.mindat.org/loc-3551.html Mineralogy Database - Minerals, Locations, Mineral Photos and Data]
* [http://dsc.discovery.com/news/briefs/20050530/arseniceater.html Discovery of Arsenic Eating Microbe]
* [http://www1.iwvisp.com/tronagemclub/SiteMap.htm Searles Lake Gem and Mineral Society]
* [http://www.blackturtle.us/DV_SITES/SEARLES/ Searles Valley Information at blackturtle.us]
* [http://maps.google.com/?ie=UTF8&ll=35.730349,-117.333641&spn=0.10298,0.22831&t=k&z=13&om=1 Satellite Photo (Google Maps)]
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