Lithium is soft and silvery white and it is the least dense of the metals. It is highly reactive and does not occur freely in nature. Freshly cut surfaces oxidize rapidly in air to form a black oxide coating. It is the only common metal (but see radium) that reacts with nitrogen at room temperature, forming lithium nitride.
Melting point: 180.5 °C Boiling point: 1342 °C
A sheet is a flat material with a thickness larger than foils.