The density of beryllium is 1,848 kg m-3. Beryllium is a dark gray metal whose atomic number is four and whose melting point is 2,349 degrees Fahrenheit. Its boiling point is 4,476 degrees F.
Beryllium is a strong, hard metal, although it is the lightest in weight of any of the rigid metals. It's mostly found in beryl crystals. Precious stones, such as emeralds and aquamarines, are also types of beryl.
The metal is alloyed with other metals, such as copper, nickel and aluminum, to make them stronger, tougher and more wear resistant.
Beryllium was once called glucinum because it tasted sweet like sugar. However, beryllium and its compounds are poisonous.