What are enamel coffee mugs made out of?

Enamel coffee mugs are typically made from a metal base, often steel or aluminum, that is coated with a layer of enamel. The enamel is a glass-like substance that is fused to the metal through a high-temperature process, creating a durable and heat-resistant surface. This coating not only provides a smooth, easy-to-clean finish but also adds a colorful and decorative element to the mugs. The combination of metal and enamel makes these mugs lightweight yet sturdy, ideal for both outdoor and everyday use.