If you look at a piece of shiny metal, say gold, it will appear to be even and smooth throughout. However, the fact is that all solid metals are made up of crystals. These crystals are far too small to be seen with the naked eye. Moreover, when the metal is polished, the metal atoms are spread over the surface rather like butter being spread over a slice of bread. This is why the metals appear smooth. If the serface layer is scraped away, the small crystals, which make up the metal can be clearly seen under a microscope.
