[akaivyleaf]

I would do it with an old pan that you won't be using to cook food. They say crayons are non-toxic but why tempt fate.

I've done the same thing with candy molds in the microwave for other shaped crayons. Kids in Vacation Bible School love them. I generally get tasked for making crayons every year. I do varigated colors.... Pink on the top, green on the bottom, you can get very creative.