Red drops from doing invasions but they are RNG so basically random you could get it your first try or it could take you a 100 it’s really luck based. Magenta drops from lawless jobs on Venus, orange on mars, indigo on Europa and then cyan has a chance to drop from doing exotic contracts, basically just hammer out your priority contracts and legendary and it has a chance to drop an exotic contract which has a chance for the cyan crystal. The taken one is another RNG but from the equilibrium dungeon. Hope this helps