Metals are crystalline when in the solid form.
The crystal structure of a solid metal refers to the internal structure or arrangement of the atoms in an ordered, repeating, three dimensional pattern. Normal metallic objects are polycrystalline, which means they consist of an aggregate of many very small crystals. These crystals are called grains. Some metallic objects, such as castings, have very large grains that can be resolved with the naked eye and these structures are referred to as macrostructures. Typically, the grains of a metal object are very small, and can not be viewed with the naked eye.