The third hardest element on Earth. Crystalline boron yields only to diamond and cubic boron nitride. Boron carbide plates stop rifle bullets. And boron is the secret ingredient in Pyrex glass — a dish made from it won't crack even when you pour boiling water over ice-cold glass.
Boron is a metalloid, a semiconductor, and a trace element that plants need to bloom. Its compounds protect homes from insects, clean clothes, and control nuclear reactors. A small element with an outsized impact on everyday life.
Boron never occurs as a free element in nature — only within minerals like borax (sodium borate) and colemanite. The largest deposits are in Turkey, which controls about 70% of global reserves. Pure boron is obtained by reducing the oxide with magnesium or by electrolysis.
Elemental boron exists in several allotropic forms. The most stable — beta-rhombohedral boron — is extremely hard and chemically resistant. This makes it indispensable for abrasives, ceramics, and armor materials.
Boric acid in small doses is relatively safe and is even used as an eye antiseptic. However, ingesting large amounts (over 15 g) is toxic. Elemental boron dust irritates the respiratory tract and eyes. When handling fine boron powder, a respirator and safety goggles are required. Borohydrides are toxic and flammable, demanding careful handling.
Boron carbide (B₄C) is the third hardest material in the world. It's used in body armor and helicopter protection. A 7.62 mm bullet can't penetrate a 12 mm plate.
Boron burns with a bright green flame. Pyrotechnicians use boron compounds to create green fireworks — one of the most vivid colors in the sky.
Boron-10 absorbs neutrons better than almost any other stable element. That's why boron serves as the main 'brake pedal' in nuclear reactors.
Without boron, plants cannot flower or bear fruit. Even a tiny deficiency in the soil causes deformed roots and dying growth tips.
Boron wasn't forged inside stars. It was created in space when cosmic rays smashed carbon and oxygen nuclei into smaller atoms — a process called cosmic ray spallation.
The world's strongest permanent magnets — neodymium magnets (NdFeB) — contain boron. Without them, earbuds, electric motors, and hard drives wouldn't work.
| Isotope | Mass (u) | Abundance | Half-life | Decay |
|---|---|---|---|---|
10B | 10.012937 | 19.90% | stable | — |
11B | 11.009305 | 80.10% | stable | — |
Electrolysis and chemical reduction