A crystal is made up of a large number of particles packed together in a repeating pattern. This structure is called a crystal lattice. The particles that make up a crystal can be;

• Ions
• Atoms
• Molecules

1. Giant Ionic Lattice (Eg: Na⁺, Cl^-)

Here, Cations (Na⁺) are packed together in a repeating pattern to form the Na⁺ and Cl^- crystals. This lattice is held together by ionic bonds.

2. Giant Atomic Lattice (Eg: diamond)

In an atomic lattice, large number of carbon atoms is arranged in a repeating pattern. These carbon atoms are held by covalent bonds. Another example is in graphite.

3. Giant Molecular Lattice (Eg: solid CO₂)

It is held together by weak Vander Waals forces. Giant molecular structures don’t conduct electricity because they are made of molecules.

4. Giant Metallic Lattice (Eg: Mg)

Metals are crystals. They consist of a giant lattice of metal cations (Mg) with delocalized electrons moving freely between the metal ions.