December birthstones: turquoise, tanzanite, zircon
December has three accepted birthstones — turquoise and zircon historically, with tanzanite added by the American Gem Society in 2002. All three trend blue, but they’re otherwise nothing alike.
The three options
| Hardness | Color | Best for | |
|---|---|---|---|
| Turquoise | 5–6 | Sky-blue, sometimes with brown veining | Distinctive, Southwestern-style aesthetic. Often set in silver. Too soft for daily-wear rings; lovely in pendants and earrings. |
| Tanzanite | 6.5–7 | Vivid violet-blue (trichroic) | Modern milestone birthstone. Single Tanzanian source approaching geological exhaustion. See the tanzanite guide. |
| Zircon | 7.5 | Most often heat-treated to sky-blue or teal | The daily-wear-durable December stone. Not to be confused with cubic zirconia. See the zircon guide. |
For most December birthstone gifts: tanzanite for milestone occasions (birthdays in the 30s and beyond), zircon for daily-wear practicality, turquoise for someone whose existing aesthetic is bohemian or Southwestern.
See the deeper guides: tanzanite and zircon.
Browse zircon
Browse turquoise
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Browse tanzanite
More from the birthstones guides
Written by
Anna
Jeweler · Formi Jewelry
Anna works with Formi clients on stone selection, setting design, and fit — making sure every piece is right before it’s made.
Book a consultation with our in-house jewelersLast updated May 2026