And examples include ice. In other words, when you freeze ice, when you take energy away from water and form ice, the water molecules form a very structured formation. And this creates what we know as ice. And ice are called molecular crystals or molecular solids. The fourth and final type of Crystalline Solids we're going to look at are network covalent crystals. Now, these consist of network of atoms or molecules held together by covalent bonds.