What is the main purpose of refining a metal after it has been extracted?

The main purpose of refining a metal after it has been extracted is to remove impurities from the extracted metal. Metals extracted from their ores using standard reduction processes are often in an impure state known as crude metal. These crude metals contain various impurities, such as other metals, non-metals like carbon, silicon, or sulphur, or leftover slag. Common refining methods include electrolytic refining, zone refining, liquation and distillation.