Enamel is a glass-like coating made by melting various substances and applying it to metal surfaces to protect and add shine. Historically, enamel was first used in ancient Greece in the 5th century BC to decorate gold ornaments. It became more widespread after the industrial revolution made enamel production easier. Enamel products can last for years if properly cared for, as enamel is resistant to temperatures up to 220-250 degrees and durable enough to withstand washing and normal use without breaking if not subjected to force. The document provides examples of enamel products for sale including colanders, mugs, and teapots.