green&blue.
We're all Gems, but some of us are Diamonds — those are our leaders. Yellow, Blue, White, and — well, Pink Diamond got shattered.
Um. certain gems are made from certain substances and peridots come from deep within the mantle of a planet. The only gem stronger than peridots are diamonds. Peridots are used for a lot of things, but we're typically the more logical and technically savvy of Gems.