Besevrona for Amethyst, Alnitans for Sapphire, Alcyon for Ruby(T6), Cardass for Topaz(T6), and Shedu Tier for Emerald(T6).
Amethyst under shallow water, like along coasts at low Alt(5-40)
Sapphire in Mountains at higher alts(40-110)
Ruby under deserts and close to lava at low alts(5-40)
Topaz in mountains at high alt(110-150)
Emerald under deep water like oceans/seas at low alt(5-40)
Each gem has a “twin” that can be found on the same planet. Diamond and Ruby, Amethyst and Emerald, and Sapphire and Topaz.
Hope this helps you guys get past that hump. Always glad to be of service