Giant Metallic Lattice
Metallic structures are composed of a lattice of positive ions in a sea of delocalised valence electrons. Electrostatic attraction between the delocalised electrons and the positive ions holds the structure together.
High melting point - a lot of energy is required to break the bonds of strong electrostatic attraction.
Good electrical conductivity - electrons are mobile, so are free to carry a current.
Example of Metallic stucture.