When you look at the shiny surface of a metal like gold, you will feel that it is smooth and even throughout. But in reality, it is not so. Metals appear to have a smooth surface because they are polished.
All solid metals are made up of crystals so small that they cannot be seen by the naked eye. When we polish a metal, the atoms spread on its surface just like butter on a slice of bread. This is why the metal appears smooth. If the surface layer is scraped away, the small crystals, which make up the metal, can be clearly seen under a microscope.
In addition to this, pure metals are either too soft or brittle and are chemically reactive for use. Hence they are often combined with several other substances in different ratios to modify them for our use.
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