The electrons are the children at the picnic, running around fairly wildly, and only loosely bound to any one adult. The reason metals conduct electricity so well is that their electrons are so free to move. Crystallization Crystallization is the process which forms crystals and minerals. Here's a very brief description with an idealized example. Start with a liquid containing some ions, for example a glass of salt water.
Salt water contains sodium and chloride ions.
Either cool the liquid or slowly evaporate it. If you leave your glass of salt water out in the sun, the water in it will begin to evaporate, and the concentration of sodium and chloride ions in the water will increase. Eventually, enough water leaves that the concentration of ions reaches saturation, the point at which the ions can only just remain dissolved. As still more water evaporates, the ions must begin to precipitate out into solid form, as sodium chloride. Ions coalesce into a regular repeating arrangement.