Birthstone for the Month of December: Turquoise, Tanzanite, Zircon & Blue Topaz Explained (2026)

Unlike most months, December was never assigned just one birthstone. Long before gemological trade groups got involved, turquoise had already been worn as December's stone for generations across multiple cultures. In 2002, the American Gem Trade Association and Jewelers of America added tanzanite, zircon, and blue topaz to the official list — partly because turquoise, an opaque and relatively soft stone, isn't the easiest match for modern ring and everyday-wear settings. That's why anyone born in December actually gets to choose from four legitimate birthstones instead of being locked into one.

The Four December Birthstones, at a Glance

December's four official birthstones are turquoise, tanzanite, zircon, and blue topaz — one traditional stone and three modern alternatives, each with a distinct color, hardness, and price point. Turquoise is the historic choice; tanzanite is the rarest and most prized; zircon is the most commonly confused with a different stone entirely; and blue topaz is the most practical for daily wear. Below is a breakdown of each.

Turquoise — The Traditional December Birthstone

Turquoise is December's original, traditional birthstone — an opaque, sky-to-teal-blue mineral that's been used in jewelry and amulets across Persian, Egyptian, Native American, and Tibetan cultures for thousands of years. Its color comes from copper and iron content, and no two pieces of natural turquoise look exactly alike, which is part of its appeal. At roughly 5 to 6 on the Mohs hardness scale, turquoise is softer and more porous than most gemstones, so it can absorb oils and discolor over time and scratches more easily than a stone set in a ring meant for daily wear. It's better suited to pendants, earrings, and occasional-wear pieces than something you'd want banging around all day.

Tanzanite — The Rare Modern Birthstone

Tanzanite is a deep blue-to-violet gemstone found in only one location on Earth — a small mining area near Mount Kilimanjaro in Tanzania, which is also where it gets its name. It was discovered in 1967 and added as an official December birthstone in 2002. Tanzanite is pleochroic, meaning it can show different colors (blue, violet, even burgundy) depending on the angle it's viewed from, which is part of what makes cut tanzanite so striking. It sits at around 6 to 6.5 on the Mohs scale, making it noticeably more delicate than a stone like topaz or sapphire, so it's generally recommended for pendants and earrings rather than an everyday ring.

Zircon — The Most Misunderstood December Birthstone

Zircon is a naturally occurring gemstone, not a synthetic diamond substitute — despite the name sounding almost identical to cubic zirconia, the two are completely different materials. Natural blue zircon has one of the highest refractive indices of any gemstone, giving it a brilliance and fire that rivals stones costing far more. It ranks about 6 to 7.5 on the Mohs scale and most blue zircon on the market has been heat-treated to bring out its color, which is a standard, accepted practice in the gem trade. Because the name confusion is so common, it's worth double-checking with a jeweler which stone you're actually buying.

Blue Topaz — The Most Affordable and Durable Option

Blue topaz is the most practical of December's four birthstones for everyday jewelry, combining strong durability (8 on the Mohs scale, the same as natural topaz in any color) with a price point well below tanzanite or fine turquoise. Most blue topaz on the market — including the London Blue, Swiss Blue, and Sky Blue shades — starts out colorless and is irradiated and heat-treated to reach its signature blue, a widely used and gemologically accepted process. Because it's hard, affordable, and comes in a range of blue tones from pale to deep, it's the version of December's birthstone you'll see most often in necklaces, studs, and rings designed to be worn daily rather than saved for special occasions.

December Birthstone Comparison

Which December Birthstone Should You Choose?

For everyday jewelry you'll actually wear often, blue topaz is the most practical December birthstone thanks to its durability and accessible price; for a rarer, statement-making piece, tanzanite is the standout choice. If you want the historic, culturally rich option, turquoise is the original December stone, and if you love maximum sparkle for the price, zircon is worth a look. There's no wrong answer among the four — the “right” one comes down to how often you plan to wear the piece and whether you're shopping for daily jewelry or a special-occasion statement.

AJLuxe's birthstone necklaces are handset in 925 sterling silver with 18K gold plating and designed for everyday wear, which is why blue topaz tones are the most popular pick for December pieces in that collection — they hold up to daily wear far better than turquoise or tanzanite would in the same setting.

December's Zodiac Connection

December birthdays span two zodiac signs — Sagittarius (through December 21) and Capricorn (from December 22 onward) — and each has its own separate zodiac gemstone tradition, distinct from the calendar-month birthstones above. If you're shopping by zodiac sign rather than birth month, that's a different (and often overlapping) list of stones worth checking separately before you buy.

For more on gemstone identification and treatments, the Gemological Institute of America is a reliable independent resource: gia.edu.

Frequently Asked Questions

What is the true December birthstone?

Turquoise is the true, original December birthstone, used in jewelry for thousands of years before any modern alternatives existed. Tanzanite, zircon, and blue topaz are all legitimate official birthstones too, but they were only added to the list in 2002 — turquoise is the one with the actual historical claim to the month.

Which stone is best for December born?

The best December birthstone depends on how the jewelry will be worn: blue topaz is best for everyday pieces because it's hard and affordable, tanzanite is best for someone who wants a rare statement stone, turquoise is best for those drawn to tradition and history, and zircon is best for anyone who wants maximum brilliance and sparkle.

What are the 4 birthstones for December?

The four birthstones for December are turquoise, tanzanite, zircon, and blue topaz. Turquoise is the traditional stone, while tanzanite, zircon, and blue topaz were officially added as modern options by the American Gem Trade Association and Jewelers of America in 2002.

What is the pretty birthstone for December?

Tanzanite is widely considered the most striking December birthstone because of its rich blue-violet color and the way it shifts shades depending on the light and angle. That said, “prettiest” is subjective — zircon's brilliance and blue topaz's clean, saturated blue both have their own strong appeal.

Is blue topaz a real December birthstone?

Yes, blue topaz is one of the four officially recognized December birthstones, added alongside tanzanite and zircon in 2002. It's also the most commonly used of the four in mass-market jewelry because it's significantly more durable and affordable than turquoise or tanzanite.

Is zircon the same as cubic zirconia?

No, zircon and cubic zirconia are entirely different materials despite the similar-sounding names. Zircon is a natural gemstone mined from the earth, while cubic zirconia is a lab-created synthetic material typically used as a diamond simulant.