Slag or Treasure
Metals require refining in order for them to achieve their greatest value. All metals are mined from the ground as ore, mixed in with other minerals and contaminants which diminish the purity of the metals. Regardless of the planned use of the metal, there is a process through which the raw metal ore needs to pass for it to perform at its best - this process is called refinement. There are several different processes by which metals of different types are refined, but the process that has been in use the longest, and is still widely used today, is refinement through the addition of heat. Very simply, in this type of refinement, the metal ore is placed in a crucible, a vessel which can withstand extremely high temperatures, and the ore is heated to a point where the metals within the ore are liquefied. In their liquid forms, the different metals can separate from each other by flowing past each other as they settle in different layers, and any other minerals and contaminants...