January — Garnet
Deep red, green, and orange varieties
February — Amethyst
Purple, from pastel lavender to royal violet
March — Aquamarine
Sea-blue to icy pale blue
April — Diamond
White, black, champagne, and salt-and-pepper
May — Emerald
Vivid green to bluish-green
June — Pearl / Moonstone / Alexandrite
Pearl (white/cream), moonstone (blue adularescence), alexandrite (color-change)
July — Ruby
Pigeon-blood red to pinkish red
August — Peridot / Spinel
Peridot (lime green), Spinel (pink/red/gray)
September — Sapphire
Royal blue, pastel, teal, pink, yellow, and parti-color
October — Opal / Tourmaline
Opal (play-of-color), Tourmaline (pink/green/bi-color)
November — Topaz / Citrine
Topaz (London/Swiss blue), Citrine (honey to Madeira)
December — Turquoise / Zircon / Tanzanite
Turquoise (robin’s-egg), Zircon (ice blue), Tanzanite (violet-blue)