Coppersmith extensive degree it must be annealed. This process involves heating the metal and then rapidly cooling it in water. The cooling stage is known as quenching. By heating the copper, the molecules in the metal are relaxed, and thus able to align themselves in a more uniform fashion. This allows for easier shaping of the metal. In order to keep this uniformity within the metal, it is cooled instantly. This prevents the molecules from moving around and causing tension in the structure of the metal. Unlike ferrous metals—which must be cooled slowly to anneal—copper can be cooled slowly in air
History of glass in sub-Saharan Africa be shaped, heated and cooled. The archaeological evidence of beadworking in Sub-Saharan Africa provides examples of both types.5 9 With melted glass working, beads found were generally formed by either a wound, drawn or moulded process. Wound glass beads, also known as Tubular, Cylindrical, Spherical or Melon-Shaped, were formed by folding molten glass around a metal rod called a mandrel. Once the glass had cooled slightly, the material was slipped off the mandrel and pinched and prodded until it reached a desired shape.9 Also known as Cane beads, Drawn beads were formed by dipping an iron blowpipe into molten glass