Diamond
Benitoite
Neptunite
Jade
Bort
Ventricosus (Ep 4-5)
Zircon
Sphene
Peridot
Kongô-sensei
Yellow Diamond
Amethyst
Red Beryl
Euclase
Antarcticite
Cinnabar (Cinsha)
Morganite
Heliodor (Ep 12)
Hemimorphite
Alexandrite
Padparadscha (Ep 11)
Obsidian
Goshenite
Watermelon Tourmaline (Ep 3)
Phosphophyllite (Phos)
Aculeatus (Ep 5)
Rutile
Jôji Nakata (Kongô-sensei)
Maaya Uchida (Red Beryl)
Chiwa Saitô (Ventricosus (Ep 4-5))
Mikako Komatsu (Cinnabar (Cinsha))
Hitomi Nabatame (Sphene)
Sayaka Harada (Watermelon Tourmaline (Ep 3))
Reina Ueda (Hemimorphite)
Mamiko Noto (Euclase)
Mutsumi Tamura (Morganite)
Ayane Sakura (Bort)
Rie Kugimiya (Alexandrite)
Tomoyo Kurosawa (Phosphophyllite (Phos))
Ai Kayano (Diamond)
Atsumi Tanezaki (Neptunite)
Ari Ozawa (Benitoite)