Definition of slag

The word "slag" comes from the Old Norse word "slagg," meaning "forsome matter" or "cinder." This word was borrowed by the Old English language and transformed into "slach" or "slæg." The term eventually made its way into Middle English as "slakk," and eventually evolved into the word "slag" that we use today. In metallurgy, slag refers to any impure material that separates from a metal during its production. It can be either a solid or a liquid substance that forms above or below the molten metal. The impurities in ore are often removed through smelting, a process that involves heating the ore to separate the valuable metallic elements from the unwanted substances. The resulting molten mixture is called "slag" if it is rich in silica or lime and is therefore separated from the desired metal. The separation of slag is crucial to the efficiency and quality of the metallurgical process, as it allows for the production of pure, high-grade metal.