Silver Tongue
I never notice until now that N° of gems = N° of individual gem components, you know Garnet have 2 gems (ruby [1] + saphire [1]), and Stevonnie 1 [Steven [1] + Connie [0]). so~ I think aside of eyes, gem number could help identify the nuber of gem components, but something is wong here... I can't remember.
Anonymous

Fusions show how many gems there are fused.  The sote of the gems base form will be where it is in fusion. Like opal having a gem on her forhead (pearl) and a gem on her chest (amethyst)