I just did a quick search and found out that Sulfur melts at 112.8° C (235.04° F) Another site said it melts at 115.21°C (239.378° F)
Sulfur boils at 444.7°C (832.46°F) I don't know when the vapor begins, but would assume it would be somewhere after melting and before boiling. I thought I may have melted or boiled the sulfur in my powder before, but after reading this, I don't think so. I don't think I've ever had it above 200° F. It's an interesting point to keep in mind, if you heat your pucks to dry them, like I do. I generally use a dehydrator to dry them. I think 146° F is as high as it goes. In the summer, as someone suggested earlier, I now dry them on the dash of my hot pickup. It works really good, up over 130°f.