Searlesite is a

sodium Sodium is a chemical element with the symbol Na (from Latin ''natrium'') and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable iso ...

borosilicate Borosilicate glass is a type of glass with silica and boron trioxide as the main glass-forming constituents. Borosilicate glasses are known for having very low coefficients of thermal expansion (≈3 × 10−6 K−1 at 20 °C), ma ...

mineral, with the chemical formula NaBSi₂O₅(OH)₂. It was discovered in 1914 at

Searles Lake Searles Lake is an endorheic dry lake in the Searles Valley of the Mojave Desert, in northwestern San Bernardino County, California. The lake in the past was also called Slate Range Lake and Borax Lake. The mining community of Trona is on its ...

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

, and was named to honor John W. Searles (16 November 1828 - 7 October 1897), California

pioneer Pioneer commonly refers to a settler who migrates to previously uninhabited or sparsely inhabited land. In the United States pioneer commonly refers to an American pioneer, a person in American history who migrated west to join in settling and dev ...

, who drilled the well that yielded the first known Searlesite. Searlesite is usually found disseminated in fine-grained lacustrine strata and often associated with altering volcanic ash. It may be a minor component of borate deposits, but it is rarely found concentrated or in megascopic crystals and so has not been developed as an ore mineral of boron. It occurs interbedded with

oil shale Oil shale is an organic-rich fine-grained sedimentary rock containing kerogen (a solid mixture of organic chemical compounds) from which liquid hydrocarbons can be produced. In addition to kerogen, general composition of oil shales constitute ...

s or

marl Marl is an earthy material rich in carbonate minerals, clays, and silt. When hardened into rock, this becomes marlstone. It is formed in marine or freshwater environments, often through the activities of algae. Marl makes up the lower part o ...

s (

Green River Formation The Green River Formation is an Eocene geologic formation that records the sedimentation in a group of intermountain lakes in three basins along the present-day Green River in Colorado, Wyoming, and Utah. The sediments are deposited in very fine ...

, US) and in

boron Boron is a chemical element with the symbol B and atomic number 5. In its crystalline form it is a brittle, dark, lustrous metalloid; in its amorphous form it is a brown powder. As the lightest element of the ''boron group'' it has th ...

-bearing

evaporite An evaporite () is a water-soluble sedimentary mineral deposit that results from concentration and crystallization by evaporation from an aqueous solution. There are two types of evaporite deposits: marine, which can also be described as ocea ...

deposits (California, US); rarely in

vug A vug, vugh, or vugg ( ) is a small- to medium-sized cavity inside rock. It may be formed through a variety of processes. Most commonly, cracks and fissures opened by tectonic activity (folding and faulting) are partially filled by quartz, ...

s in

phonolite Phonolite is an uncommon extrusive rock, of intermediate chemical composition between felsic and mafic, with texture ranging from aphanitic (fine-grained) to porphyritic (mixed fine- and coarse-grained). Phonolite is a variation of the igneous ...

(Point of Rocks,

New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe , LargestCity = Albuquerque , LargestMetro = Tiguex , OfficialLang = None , Languages = English, Spanish ( New Mexican), Navajo, Ker ...

References

Mindata, with localitiesWebmineralSearlesite

Borate minerals Phyllosilicates Monoclinic minerals Minerals in space group 4 Searles Valley Geology of Inyo County, California Borosilicates {{silicate-mineral-stub