Waxes have been used to make metal castings since the Bronze Age. The technology to recycle these waxes has been in use since 1970. Recycled waxes have been regarded as a secondary material with perceived lower quality as most reclaimers can not match the exact physical and dimensional characteristics as the virgin pattern wax. This is because the hydrocarbon waxes and resins break down when exposed to heat during the casting process. Advances in chemical technology have now made it possible to repair the broken carbon chains and restore the used wax back to the same chemical composition as the virgin wax components.