Borate is the sodium substitute for potassium, and when it is high in sodium, it is called 'natroalunite.'
The History Says
Borates additional applications were discovered when, by 1830s, scientists understood the pharmaceutical uses of boric acid. The subsequent generation discovered enameling of iron, preserving meats, harden plaster, making glass heat resistant, and cleansing with borates.
The Present Scenario
Most of the borates in the world are supplied by Rio Tinto Borax from the southern United States. Death Valley in California is famous for borate mining. Atacama Desert in Chile also contain mineable borate concentrations.
BORATE IS a compound of the borate ion with metallic elements. The boron found in nature is usually in the form of borate mineral. It is sometimes also combined with silicate and forms complex borosilicate minerals like tourmalines.
There are different forms of existence of borate. The acid condition is known as boric acid (H3BO3). The basic conditions occur like dihydrogen borate ion H2BO3-. The hydrogen borate ion is HBO32- and borate ion is BO33-.
Borate forms many polymeric ions. The common is tetraborate ion, B4O72-. The hydrogen tetraborate ion is HB4O7-. It also occurs as triborate and pentaborate. Various metaborate ions have an empirical formula of BO2- and forms metaborate compounds.
The usual borate salts include sodium metaborate (NaBO2) and sodium tetraborate (Na2B4O7). Sodium tetraborate even occur naturally as hydrous mineral borax (Na2B4O7·10H2O)
Principal Sedimentary Borate Minerals
| Mineral | Formula | B2O3 content (wt%) |
| Primary Borax Ulexite | Na2O·2B2O3·10H2O Na2O·2CaO·5B2O3·16H2O | 36.5 43.0 |
| Secondary Kernite Ulexite Colemanite | Na2O·2B2O3·4H2O Na2O·2CaO·5B2O3·16H2O 2CaO·3B2O3·5H2O | 51.0 43.0 50.8 |
| Szaibelyite | Liaoning Province (China) 2MgO·B2O3·H2O | 41.4 |
Formed by Precipitation from Cooling Hot-Spring Fluids Argentina and Death Valley (United States)
| Mineral | Formula | B2O3 content (wt%) |
| Primary Ulexite | Na2O·2CaO·5B2O3·16H2O | 43.0 |
| Secondary Proberite Colemanite | Na2O·2CaO·5B2O3·10H2O 2CaO·3B2O3·5H2O | 49.6 50.8 |
Different Types of Borate
- Borate ion - BO33-
- Boric acid - H3BO3
- Dihydrogen borate ion - H2BO3
- Hydrogen borate ion - HBO32-
- Tetraborate ion - B4O72-
- Hydrogen tetraborate ion - HB4O7
- Sodium metaborate - NaBO2
- Sodium tetraborate - Na2B4O7
- Hydrous mineral borax - Na2B4O7.10H2O
- Trimethyl borate - B(OCH3)3
Common Borate Minerals
- Kernite - Na2B4O7.4H2O
- Borax - Na2B4O7.10H2O
- Ulexite - NaCaB5O9.8H2O
- Colemanite - Ca2B5O11.5H2O
Main Sources of Borates
Most of the borates in the world are supplied by Rio Tinto Borax from the southern United States. The company was established by Francis Marion Smith in 1883 which was then known as The Harmony Borax Works. In 1872, Mr. Smith found borates in the Nevada desert.
Death Valley in California is famous for borate mining. Atacama Desert in Chile also contain mineable borate concentrations.
Borate's various forms are used as wood preservatives. Borate esters is used as a precursor to boronic esters for Suzuki couplings. It also includes trimethyl borate, B(OCH3)3.