Love the name!
Have you seen the cartoon Steven Universe?
Gemsona is a term used by fans of the show who created their own version of a Crystal Gem based off of a stone they like, it can either be a single gem/stone/crystal (whatever you prefer) or it can be a fusion between a few different ones (like Sapphire and Ruby who fuse to make Garnet or when Garnet fuses with Amethyst to make Sugilite). It's basically a gem/stone/crystal who takes on a somewhat human like appearance, for example my gemsona is based off of a cut Chrysoprase; gems can be cut or uncut and must be placed somewhere on their body, they can store basically anything inside their gem like weapons or just things they like or find useful.