Can You Melt Wax in a Microwave?

Q: I tried melting wax in a microwave, but it didn’t even get warm. Why not?

—J.W., Cary, Ill.

Microwave ovens target the water in food in order to heat it. Waxes have no water, so they don’t get hot. (Metals are different—although they also have no water, the behavior of their surface electrons may cause the microwaves to be reflected and arc inside the oven, which can damage it.) To melt wax, you need a double boiler for effectiveness and safety. Never try to melt wax with direct heat, such as placing it in a pot on a range top. The temperature can rise quickly at a certain point and produce extremely flammable vapors. Also, hot wax may spatter.