Quartz is a covalent crystal.
Solids with a typical geometry are known as crystalline solids. In such type of solids, there are definite arrangements of particles throughout the 3-dimensional network of a crystal in a long-range order.
Many non-metal crystalline solids form covalent bonds between neighbouring atoms in the crystal, forming a giant molecule or large molecules.
- These solids are hard like diamond and soft like graphite which are isotopes of carbon.
- They are insulators as in the case of a diamond but in case of graphite due to free electrons, they conduct electricity and act as a conductor.