The gems in Steven Universe had a cool thing going on where the location of their gem on their body acted as symbolism.
Pearl's gem is on her forehead, signifying her intelligence.
Amethyst's gem is on her chest, close to the heart (if she had one), signifying her passion.
Garnet's gems are in her hands, a visual of her strength.
Jasper's gem is her nose because snff snf snf snff