Natural medium dark blue sapphire.
Sapphire, emeralds and rubies.
Ruby, sapphire, emerald, spinel, tourmaline, opal, aquamarine, chrysoberyl, alexandrite, cats eye, zircon, garnet, hessonite garnet, amethyst, tanzanite, green garnet (savourite), peridot, quartz, beryls, green beryl.