Boron
Boron was named for the mineral borax, thought to come from the Persian name, “burah,” for that mineral. There are over 200 minerals which contain boron, but only few such as colemanite and borax are commercially important. Borax was first extracted from dry lakebeds in Persia and Tibet and traded to Arabia and India over a thousand years ago. Today 75% of all borax production occurs in either the U.S. or Turkey. Boron is used to make glass, ceramics, and enamels, including fiberglass for insulation.
Type
Element (Minerals/Ores of)
Mineral Classification
Borates
Chemical Formula
CaB3O4(OH)3·H2O (colemanite), Na2B4O5(OH)4•8(H2O) (borax)
Streak
White
Mohs Hardness
4.5 (colemanite), 2-2.5 (borax)
Crystal System
Monoclinic (both)
Color
White, colorless, clear, gray
Luster
Vitreous
Fracture
Conchoidal
Description
Boron was named for the mineral borax, thought to come from the Persian name, “burah,” for that mineral. There are over 200 minerals which contain boron, but only few such as colemanite and borax are commercially important. Borax was first extracted from dry lakebeds in Persia and Tibet and traded to Arabia and India over a thousand years ago. Today 75% of all borax production occurs in either the U.S. or Turkey. Boron is used to make glass, ceramics, and enamels, including fiberglass for insulation.
Relation to Mining
IMAR 7th Editon
History of Boron Mining:
The early prospector’s test for borate was to wet the sample with sulfuric acid and alcohol and then light the fumes; “She burns green!” was the result of a successful boron test. Wetting a sample in turmeric or cobalt-nitrate solution is still a quick positive or negative field test. Today commercial laboratories use atomic absorption (AA) or inductively coupled plasma (ICP) methods. Its pale green phosphorescence may be related to the early prospector’s tests.
In the mid-19th century, large borax deposits were discovered in both North and South America. F.M. “borax” Smith popularized borax by expanding usage into consumer products including soaps and detergents. As a result, several California borax mines were opened. It was in one of these California mines where colemanite was first discovered. It was named after William Tell Coleman (1824-1893), the owner of the mine where it was discovered. More discoveries in the 20th century, including those in Death Valley, Boron California and Turkey, made this once rare mineral a major world-wide commodity.
Borax Mining:
Most of the major borate deposits in the world are mined by surface methods, generally using truck and shovel or backhoe equipment. In the United States, only one company in Death Valley operates underground at this time. Several mines in Turkey, and all of the ones in eastern China, are mined underground using labor-intensive methods. A few of the South American and Chinese salars (a salt-encrusted area that may be the basin of an evaporated lake) continue to use hand-mining methods to recover the thin borate layers.
Borax Brines Mining:
The U.S. and Chile also produce borates by pumping and refining complex brines; another U.S. location uses acid dissolution of in-situ colemanite as their mining method.
Uses
Boron compounds are used for many different purposes in industry and the home. In the United States, boron is used to make glass, ceramics, and enamels, including fiberglass for insulation.
Boron compounds are used to make water softeners, soaps and detergents. Other uses are in agricultural chemicals, pest controls, fire retardants, fireworks, medicine, and various minor applications.
Boron is a chemical used to make boron nitride, one of the hardest known substances, for abrasives and cutting tools.
The effect of boron on animals is under study. There is no evidence that boron is necessary for animal health, although in small quantities it might stimulate bone and muscle growth. On the other hand, it is an essential trace element for green algae and higher plants used in agriculture.