- X-ray windows (berllium transmits X-rays 17 times better than aluminium
- as a 2% alloy with nickel for springs, electrodes and nonsparking tools
- berllium (2%) alloyed with copper gives a hard strong alloy with high resistance to wear used in gyroscopes, computer parts, and instruments (desirable lightness, stiffness)
- alloys are used as a structural material for high performance aircraft, missiles, spacecraft (such as the USA space shuttle), and communication satellites.
- as a moderator in nuclear reactions since it is a highly effective moderator and reflector for neutrons
- the oxide is used in the nuclear industry
- used in flares and pyrotechnics, including incendiary bombs. It was used in flash photography,
- it is lighter than aluminium, and is used in alloys used for aircraft, car engine casings, and missile construction
- it is used a reducing agent for the production of uranium and other metals from their salts
- the hydroxide (milk of magnesia), chloride, sulphate (Epsom salts), and the citrate are used in medicine
- magnesium oxide is refractory and used as bricks and liners in furnaces
- used to make organomagnesium compounds (Grignard reagents), useful in organic synthesis
- used in computers for radio-frequency shielding
- reducing agent for the preparation of metals such as thorium, uranium, zirconium, etc.
- deoxidiser, desulphurizer, or decarbonizer for various alloys
- alloys of calcium with agent for aluminium, beryllium, copper, lead, and magnesium have some useful properties
- “getter” for residual gases in vacuum tubes, etc.
- quicklime (CaO) is made by heating limestone (CaCO3) and changes into slaked lime, Ca(OH)2, on the addition of water. It is a cheap base for the chemical industry with many uses.
- calcium from limestone is a component of Portland cement. Mixed with sand it hardens as mortar and plaster while taking up carbon dioxide from the air
- the solubility of the carbonate in water containing carbon dioxide results in stalactites and stalagmites (Cheddar Gorge) and hardness in water.
- fireworks (red flame), flares
- 90Sr is a radioactive isotope produced by nuclear fallout. 90Sr has the potential for use as lightweight nuclear producing electricity
- used to produce glass for colour television tubes
- refining zinc
- optical materials
- the sulphate, as permanent white or blanc fixe, is used in paint, in X-ray diagnostic work (BaSO4)
- barite is extensively used as a weighting agent in oil well drilling fluids, and in making rubber
- the carbonate is a rat poison
- the nitrate and chlorate give green colours (CARE!) in pyrotechnics
- sulphide is a white pigment
- making rubber
- rat poison
- self-luminous paints
- neutron sources
- medical uses for the treatment of conditions such as cancer (now being replaced by 60Co sources)