Pig iron is a crude form of iron that is produced from iron ore in a blast furnace. It contains a high percentage of carbon, typically around 3-4%, along with other impurities such as sulfur and phosphorus. This makes pig iron brittle and not suitable for direct use in most applications. Instead, it serves as an intermediate product that can be further refined into more useful forms of iron and steel. The name "pig iron" comes from the traditional method of casting the molten iron into molds that resemble a row of piglets. Once cooled, these molds would be broken apart to retrieve the pig iron. This material is often used as a raw ingredient in the production of steel and other alloys, making it an essential component in the metallurgy industry.