Vitreous enamel is an ancient art form that dates back to at least the 13th-century BCE when Mycenaean period goldsmiths created rings with inlaid enamel. 

Around the 5th-century BCE the Greeks were also using inlays of enamel glaze in sculptures.

It has been seen around the world through various ages and cultures.

Vitreous enamel is basically fine powdered glass that is sifted or poured in a painterly way onto a metallic substrates and fired at high temperatures, between around 1450°F to 1500°F using a kiln or torch. Enamel is able to fuse to pure gold, fine silver and pure copper. It is a simple medium to learn but difficult to master. In my studio I primarily use 16-18g copper but sometimes utilize copper foil, fine silver wire and/or 23k gold leaf in my designs.