The element was first isolated by Sir Humphry Davy in 1807 and by Joseph Gay-lussac and Louis Thenard in 1808.Research suggests that boron may be nutritionally important. Apparently it helps to maintain appropriate body levels of minerals and hormones needed for bone health. The low electrical conductivity of boron increases greatly as its temperature is raised. At certain temperatures, therefore, boron behaves as a semiconductor, and it is often added to germanium and silicon to increase their electrical conductivity. The use of cubic boron nitride as a high - temperature semiconductor is also being explored. Small additions of boron to steel appreciably increase the hardness of the alloy. Boron is also used in the production of pure, strong metals to remove the oxygen and nitrogen dissolved in the metal or chemically bound to it, and it is used to absorb fast neutrons in nuclear reactors.
The most important boron compound is borax, which has been used in pottery glazes since the Middle Ages. Borax deposits were first found in Tibet, and borax was brought to Europe by the Arabs. It is still important in the ceramic industry. Borax combines with chromium, copper, manganese, cobalt, and nickel to form beautifully colored compounds. Borax beads were once used as a reagent in the detection of these elements. Borax is also important in the production of borosilicate glass, which has a high refractive index and is suitable for the manufacture of lenses. Other applications of borax include the impregnation of textiles and wood to make them fire resistant; softening water for laundry; and as a flux in brazing (dissolution of oxides). A weak base, borax is also used in buffer solutions and photographic developers. Since boron is important in the calcium cycle of plants, borax or boric acid is often added to boron poor soils as a fertilizer. Boric acid is obtained by the action of strong acids on borax and is used as a mild disinfectant. Although its toxicity is low, it is not completely harmless. Its use as a food preservative is prohibited in many countries.