Beryllium is in group 2 of the periodic table, so it is an alkaline earth metal. It is grayish (slightly gray) in color. It has an atomic number of 4 and is symbolized by the letters Be. It is toxic and should not be handled without proper training.
Beryllium, crystalline fragment
Beryllium has 4 electrons, 4 protons, and 5 neutrons.
Beryllium has a melting point of 1287 degrees Celsius (2349 degrees Fahrenheit) and a boiling point of 2970 degrees Celsius (5378 degrees Fahrenheit).
Beryllium has one of the highest melting points of the light metals. It is added to other metals to make stronger alloys. Beryllium-copper alloy is used in tools because it does not make sparks.
At standard temperature and pressures beryllium resists oxidation when exposed to oxygen.
Beryllium is best known for the chemical compounds it forms. Beryllium combines with aluminium, silicon and oxygen to make a mineral called beryl. Emerald and aquamarine are two varieties of beryl which are used as gemstones in jewelry.
Since it has a very high stiffness to weight ratio, beryllium is used to make the diaphragms in some high-end speakers.