I love the new cartoon, Steven Universe, it's super cute! So I wanted to make my own gem. I came up with Opal. Since there are so many different types of Opals, I went with the most well known and it's the African White Opal. It's white and they can vary with the different colors they shimmer. I have one that was given to me as a gift, so I went with the colors in that one and they were green and orange. And, technicaly, I don't think the Opal is considered a crystal gem at all, but I wanted to do this one since it's unique.
Her gem is on her tongue because Opals are fragile and I wanted it somewhere unique, and as you can see from the picture, her weapon is a bow and arrow.