Yeah. That's why I wrote it is simplified and generalised. They are different types of those medals. The universal one is a circle- from a wreath which is a symbol of honour. If you google different country it might change- it can be cross, a star or circle or something else- depending of political and historical background. It also does not have fully circle shape. Star in pixels as a "symbol" is difficult to pull off and then will look inappropriate or inadequate.
Grab a pen or try to change existing sprite and try to draw it using single lines and tell me how does it look.