I've never used either to pour wax into but I use the platic portion cups you get from like a restraunt and those don't melt so I would think these would be just fine. I did try using the little metal containers that come in alittle case a long time ago to make up a sample set of scents but I wasnt happy with those, they just seemed so small so now I just have a bag filled with 1oz portion cups, each labeled with the scents and that works great. Sandy