Peace, Earthlings!

(blushing, embarrased) Aw shucks, Steven! Cut it out....

Usually Gems are made, not born! Colorful goo stuff is put super deep in the ground, and after lotsa time and pressure, a Gem gets formed. When we're ready, we glow and make a body for the first time, and pop out of the ground! We come out just like we are, and then pretty much stay that way forever. We don't have to bother growing up like humans do!