I think there are a lot of misconceptions about what enamel is.
There's a type of paint called Enamel Paint, and that throws a lot of folks off. There are also pins that claim to be enamel, but are actually paint, plastic, or resin that are designed to look like an enamel technique called champleve.
I get a ton of folks at in-person events asking what my pieces are made of. They ask if it's paint or pottery. So here goes...
The type of enamel that I work with is called Vitreous Enamel. It's a powder glass that fuses to metal at about 1450 degrees.
You can enamel copper, fine silver, or 24k gold, and you can fuse it either using a torch or in a kiln.
When I teach, I like to use butane torches because they're fairly cheap, and butane is accessible to buy. You can get it at your local hardware store, as opposed to acetylene, which is a much more expensive set-up and you need to get the tanks from Air Gas. In my studio, I will often kiln-fire my pieces because I can fire multiple pieces at once. There are pros and cons to both.
One of the major pros to torch-firing when you're first starting enameling, is that you can watch the glass fuse to the metal and see the process from A to Z. You can watch the enamel go through the stages of firing: sugar coat, orange peel, to maturity (or fully fired). When you fire in the kiln, you don't get to watch all the stages and it's a little trickier knowing when the piece will be fully fused.