Wanted to try doing something free-hand and basic, wasn't the first thing that came to mind but I think it came out pretty good. :)

The Pentagram; many meanings, but I personally consider it a sign of protection and a symbol of the elements. Bottom left Earth, bottom right Fire, top left air, top right water and top center is spirit... or as some would say heart! GO PLANET!!! X3 Sorry I had to. <3