Louis-Nicolas Vauquelin first isolated the element in 1798. He identified the new earth from emeralds and beryls and noted its sweet taste. Friedrich Wöhler and Antoine Bussy independently isolated the metal itself in 1828.
Beryllium forms when high-energy cosmic rays smash into heavier atomic nuclei in the interstellar medium. It constitutes only 0.0004 percent by mass of Earth's crust and ranks as the 47th most abundant element. About one billionth of the atoms created in the early universe were beryllium-7, but these unstable isotopes decayed quickly.
Beryllium is the lightest structural metal known to science with a density of 1.85 times that of water. It exhibits exceptional stiffness with a Young's modulus of 287 gigapascals and allows sound to travel through it at speeds of about 12.9 kilometers per second. Its low density and high elastic stiffness make it a preferred material for aerospace components including the mirrors of the James Webb Space Telescope.
Inhalation of beryllium-containing dust can cause a chronic life-threatening allergic disease known as berylliosis or chronic beryllium disease. The International Agency for Research on Cancer lists beryllium and its compounds as Category 1 carcinogens. The discovery of the disease led to the discontinuation of beryllium compounds in fluorescent lighting tubes in 1949.
Beryllium-9 serves as a critical component in nuclear physics as a neutron reflector and moderator. When bombarded with fast neutrons it can undergo a reaction that releases more neutrons than it absorbs. This property was used in early atomic bombs as an initiator known as the urchin neutron initiator to trigger the chain reaction.
Industrial production began after the First World War with companies like Union Carbide and Siemens & Halske leading the way. Pure beryllium metal did not become readily available until 1957. The United States, China, and Kazakhstan are the primary producers of the metal today.