Unacceptable Gems

There are certain gemstones that have already had a canon appearance in Steven Universe and as such cannot be used again for new characters. These gems include: Remember that all of the above have exceptions that can be made, such as by using variations of that gem(eg. amethyst becomes chevron amethyst, jasper becomes ocean jasper etc).
 * Ruby
 * Sapphire
 * Pearl (unless the new character is a Pearl servant eg. Red Pearl) (only applies to youtube features)
 * Amethyst
 * Garnet
 * Rose Quartz
 * Jasper
 * Lapis Lazuli
 * Peridot (unless the new character is a Peridot technician) (only applies to youtube features)
 * Diamond (we already have one diamond, that's more than enough leadership)
 * Holly Blue Agate (other types of agate are fine as managers, but I personally don't think people would like them much to be honest)
 * Aquamarine
 * Topaz