Boron is a nonmetallic element with the atomic number 5, identified by the symbol B on the periodic table. There are a number of uses for it, and like many elements, it appears in various forms which have different potential applications. Pure elemental boron, however, is not found in nature, and it must be chemically extracted. One of the more well known uses is in the compound known as borax.
The pure form of boron is black and crystalline, and extremely brittle. A more common variant is an amorphous form, which is soft, brown, and crumbly. Boron is often used in metal refining, because it is reactive at high temperatures. Although the element is nonmetallic, it is classified as a metalloid. Metalloids are elements that share certain properties with metals, making them useful in alloys and compounds used to chemically manipulate metals.
As is the case with many elements that do not occur naturally in elemental form, it took some time for scientists to isolate boron. In 1808, several scientists succeeded in isolating one form, although they did not recognize it as an element. In the early 1900s, chemists succeeded in creating pure boron, realizing more potential applications for the element. Methods for isolation are not widely standardized, leading to varying quality when it comes to the pure form.
Plants require boron in trace amounts to be healthy, although the threshold between enough and too much is rather small. Humans and animals also ingest small amounts through the plants that they eat, but it is not believed to be a necessary trace element in human nutrition. Boron is also used in a range of industries, as a dopant, abrasive, and ingredient in propellant mixtures, among other things.
Pure boron is not itself harmful, although many of the forms in which it appears are toxic or somewhat toxic. It may naturally appear in blends of toxic material, which can make handling some forms rather harmful. In addition, boron extraction generates harmful waste, since it must be heavily treated to extract a usable pure form. Even when this material is handled responsibly, it represents a potential environmental problem, as toxins are difficult to break down into a safe and stable form. Mining companies may try to cut corners with their toxic waste, generating a major pollution problem.