Quick Answer
December has three official birthstones: turquoise, zircon, and tanzanite. Turquoise anchored the original 1912 list, zircon replaced lapis lazuli in 1952, and tanzanite joined in 2002 as one of the youngest birthstones. All three read best in pendants and earrings rather than daily rings, since tanzanite and turquoise are softer stones that reward gentler, more occasional wear.
What Are the December Birthstones?
Most months have one traditional birthstone, but December has always had more than one. The list grew over decades as trade associations expanded it: turquoise anchored the original 1912 list, zircon replaced lapis lazuli in 1952, and tanzanite was added in 2002 by the American Gem Trade Association, one of the youngest stones on any birthstone list.
- Turquoise — an opaque blue-to-green mineral and one of the oldest gemstones in continuous human use
- Zircon — a natural mineral, not to be confused with man-made cubic zirconia
- Tanzanite — a blue-violet form of zoisite discovered in the 1960s and added to the birthstone list in 2002
Tanzanite: December's Rarest and Newest Stone
Tanzanite is a form of the mineral zoisite prized for its blue-violet color, and it comes from a single source on Earth: the Merelani Hills near Mount Kilimanjaro in Tanzania. It's trichroic, showing blue, violet, and burgundy tones depending on the angle, and it measures Mohs 6 to 7 — noticeably softer than harder everyday stones.
- Nearly all tanzanite on the market is heat-treated to around 600°C to bring out its blue-violet color — a standard, industry-accepted, and disclosed step
- No true lab-grown tanzanite exists; pieces marketed as "created tanzanite" are usually synthetic forsterite or tanzanite-colored cubic zirconia, not tanzanite at all
- Better suited to pendants and earrings than everyday rings, since its moderate hardness makes it more prone to chipping on a hard knock
- Skip the ultrasonic cleaner and steam cleaning for tanzanite — a soft cloth and mild soap are the safer routine
Turquoise and Zircon: The Other Two December Stones
Turquoise and zircon round out December's birthstone trio, and each carries its own long history. Turquoise has been carved and set into jewelry for thousands of years, from ancient Persia to the Southwestern United States. Zircon is a genuinely natural mineral in its own right — not the man-made cubic zirconia it's so often confused with.
- Turquoise is opaque, ranges from sky blue to green, and sits around Mohs 5 to 6 — porous enough that it's worth keeping away from lotion, perfume, and household chemicals
- Zircon comes in blue, colorless, and warm earth tones; the blue variety sold today is almost always heat-treated, a routine and widely accepted practice
- Zircon can be brittle right at the facet edges, so it benefits from a bit of extra care during everyday wear
How to Wear a December Birthstone Look Every Day
A December birthstone tends to read best as a pendant or a pair of studs rather than a ring you knock around all day. Layer a birthstone pendant with a plain chain, add it to a stack of everyday necklaces, or let it stand alone as a simple, meaningful piece close to the collarbone.
For the everyday layer around it, here's what we make in moissanite and 925 sterling silver — a sparkling companion piece, not a birthstone substitute:
Browse the full necklaces collection for more everyday pendant styles, or see our gift guide under $100 for more ideas.
A Custom December Birthstone Piece, Made to Order
A birthstone's real meaning usually comes from a specific person, not just a calendar month. We build made-to-order pieces around that idea: a numeral or initial pendant with a genuine December birthstone accent, a small memorial design, or a piece made for one particular gift and nobody else's.
A simple bar or nameplate style like this is a natural starting point for a custom design conversation. Start a custom design inquiry and tell us what you have in mind — we'll help you turn it into a piece with a genuine tanzanite, zircon, or turquoise accent.
Caring for December Birthstone Jewelry
December's three birthstones each need a slightly different care routine because of their differing hardness. Tanzanite and turquoise are softer than everyday-wear stones like moissanite, so a little extra caution keeps them looking their best through years of regular, gentle wear.
- Put jewelry on last, after makeup, perfume, and hairspray — this matters even more for porous turquoise
- Clean with a soft, dry or barely damp cloth; skip ultrasonic and steam cleaners for tanzanite and turquoise
- Store pieces separately in a soft pouch so harder stones can't scratch softer ones
- Remove birthstone jewelry before swimming, showering, or heavy housework
For more on keeping sterling silver bright between wears, see our sterling silver and moissanite care guide.
Frequently Asked Questions
What is the December birthstone and what does it mean?
December actually has three birthstones: turquoise, zircon, and tanzanite. Turquoise has symbolized protection and good fortune for thousands of years, zircon has been cut and worn since antiquity in shades from blue to colorless, and tanzanite — the newest addition, from 2002 — is prized for a rare blue-violet color found nowhere else on Earth.
Does tanzanite only come from one place in the world?
Yes. Tanzanite is mined almost exclusively from the Merelani Hills near Mount Kilimanjaro in Tanzania, making it one of the most geographically limited gemstones sold today. That single-source origin is part of why it joined the birthstone list only in 2002, decades after it was first discovered in the 1960s.
Is zircon the same thing as cubic zirconia?
No, and this is a common mix-up. Zircon is a natural mineral that has been used in jewelry for centuries, while cubic zirconia is a man-made crystal created in a lab specifically as a diamond simulant. They share a similar-sounding name and nothing else — different chemistry, different origin, different gem entirely.
Can I wear a tanzanite ring every day?
You can, but it takes more care than a harder stone. Tanzanite sits at Mohs 6 to 7, softer than moissanite, so a ring worn daily is more exposed to knocks than a pendant or earrings would be. Many buyers choose tanzanite for necklaces and earrings for exactly this reason.
Can MYNSU make me a custom December birthstone piece?
Yes — we build made-to-order pieces with genuine tanzanite, zircon, or turquoise accents, including memorial designs and personalized numeral or initial pendants. Our ready-to-wear collection is moissanite and 925 sterling silver rather than birthstones, so for a true birthstone piece, start a custom design inquiry and tell us what you have in mind.
Every MYNSU order ships free within the US, backed by 30-day returns, and ships from our Irvine, California warehouse.