Do you know which gemstone claims the December birthstone title?
Like many other months in the year, December doesn't have just one birthstone: it actually has three (and according to some people, four).
These gemstones vary by type, rarity, cut, and price. But you'll notice one major characteristic in common: December birthstones are all various shades of blue.
Stunning gems in deep indigo to almost purple live on one end of the spectrum while the other end boasts uniquely-formed gemstones in bright robin's egg.
This wide range of gem and color choices means there's a December birthstone for every style and budget. And this resource has everything you need to discover the best birthstone for your needs. You'll find details about each gem, birthstone color, buying tips, fun facts, and much more.
Let's start with the basics:
Traditional December birthstones include lapis lazuli and turquoise. Now, modern jewelry lovers born in December have three birthstone choices: blue zircon, turquoise, and tanzanite.
Two of these options, blue zircon and turquoise, have a long history. Zircons predate dinosaurs, and the Ancient Egyptians were fond of using turquoise in jewelry and royal golden burial masks way back in 3000 BCE.
However, tanzanite is a relative newcomer to the December birthstone family. It was only discovered in 1967 -- just over 50 years ago.
Some people also believe blue topaz (as featured on our customer favorite Garen ring) should be added to the December birthstone list.
No matter which you choose, the December birthstone color is typically blue. Turquoise is generally the most affordable December birthstone (with stones rarely priced over $100), followed by zircon. Tanzanite is by far the most expensive.
Let's get to know each gorgeous gem better, starting with the most popular:
Zircon may not be as famous as gemstones like sapphire or ruby, but gem experts and geologists think it's worth a million bucks.
Why?
Because the oldest rock ever discovered on the planet happens to be a zircon (and almost 4.5 billion years old!).
Since zircon is both stunning and timeless, it became an official December birthstone in 1952, slowly pushing out the traditional lapis lazuli.
Nope!
Zircon is not the same as cubic zirconia, though many people often confuse them at first. Zircon is a natural gemstone that comes in many colors (including colorless zircon).
Cubic zirconia (CZ) is a synthetic diamond alternative. It's made in a lab to look like diamonds. So December's birthstone and CZs have no relation to each other.
Zircons have the widest color range of December birthstones, each depending on the conditions present during formation.
Colorless zircon is the purest form of this gem. The brilliance and fire of colorless zircons make them appear astonishingly similar to diamonds. Interestingly, colorless zircon is the least valuable.
Most zircons are naturally red or brown when mined, again, depending on where they form. Special heat treatments turn these zircons a vibrant blue shade.
Blue is the most sought-after zircon color and the most popular choice for December jewelry. Hues range from sky blue and teal to deep, intense violet.
Heat treatments can also create zircons in colors such as orange, yellow, and green. Many gem fanatics strive to collect zircons from different regions to snag a zircon in every color of the rainbow.
Zircons naturally form as a result of tectonic plate shifting. These events can cause mountain formations, earthquakes, and volcanoes. So it's not uncommon to find zircons in hilly regions or near sapphire deposits, which also typically form near volcanoes. Countries where Zircon and Sapphires coexist include Myanmar (Burma), Vietnam, and Cambodia.
Today, Australia claims most of the world's zircon supply. Africa is the second-largest zircon contributor (specifically, Madagascar, Mozambique, Nigeria, and Tanzania). Zircon is also mined in Sri Lanka, Brazil, Korea, and Thailand.
Most blue zircon on the market ranges from light blue to rich teal. This neutral yet bright pop of color pairs well with sterling silver and white or yellow gold. A jeweler will typically cut a zircon birthstone to show off its sparkle and add a subtle hint of glam to each piece.
Zircon ranges anywhere from 6.5 to 7.5 on the Mohs Hardness Scale, which rates the durability of gemstones on a scale of 1 (very soft) to 10 (diamond-tough). Though zircon sits somewhere in the middle, it's the highest-ranking December birthstone when it comes to hardness.
You can wear your signature zircon birthstone without worrying about it getting easily scratched or damaged during your hectic everyday activities. But to be on the safe side, try to find fine jewelry with smaller zircon stones (i.e., less surface area to get damaged).
Since zircons reflect light and change colors at different viewing angles, it can be challenging to buy a zircon online. Many zircon enthusiasts use three of the 4C's of diamond buying to evaluate each stone's price: cut, color, and clarity.
The cut should reflect each stone's unique fire and brilliance. The color should be a rich blue throughout. And there should be no visible inclusions or blemishes (as this is rare with high-quality blue zircon).
Carat weight isn't important when shopping for zircon because the price depends more on the size of the gemstone. Zircon jewelry starts at less than $100 for small stud earrings. However, rings or pendants featuring large solitaire stones may cost several hundred dollars or even top the $1,000-mark.
As the oldest December birthstone, plenty of myths, lore, and fun facts about zircon have been circulating for millennia, such as:
Now let's get to know the most traditional December birthstone...
Turquoise was one of the first gems ever discovered. It's been found in relics across the world, from Ancient Egyptian jewelry to ceremonial pieces worn by the Aztecs.
Turquoise officially became a December birthstone in 1912. Its global abundance and affordability make turquoise jewelry some of the most popular.
A turquoise stone is semi-translucent to opaque, meaning you can't see through it.
The color of each stone varies from robin egg blue to slightly blue-green or teal. Turquoise forms when mineral-rich water seeps inside certain rocks. Blue turquoise typically contains higher levels of copper, while green turquoise generally contains more iron.
On top of this base color, each turquoise stone features thin, intricate veins crisscrossing in a different color. These black, taupe, or gray lines crackling through the blue are remnants of the rock in which the turquoise formed.
These myriad combinations of minerals in the water (which form the turquoise base color) and mother rock types (which create the vein color variations) explain why no two turquoise pieces are ever the same.
Turquoise mining occurs in Mexico, Egypt, Iran, and Israel. But it's most commonly found in:
China. The Hubei Province in central China currently leads the market in sourcing and producing the most gem-quality turquoise.
The United States. Miners in the southwest have been unearthing turquoise for over a thousand years. New Mexico used to be the largest turquoise producer in the US, but Nevada and Arizona edged them out for top spots in the 1920s.
This traditional birthstone comes in all shapes and sizes, and can be smooth or rough-cut to reflect your signature style. It's the most versatile December birthstone, seamlessly transitioning your look from elevated everyday elegance to boho-chic at night.
Opal jewelry is similar in this way and can be especially gorgeous when paired with other stones like cubic zirconia.
A great example of that pairing can be found in our White Fire Champagne Opal ring!
One thing you'll want to note: turquoise is hardly ever faceted like other gemstones. It's often sliced from the rock formation it's mined from and polished. So if you're looking for a sparkly piece of turquoise jewelry, you'll need to find something with additional gemstones to score that wow factor.
Here's the bad news: turquoise may not be right for you if you're hard on jewelry. Turquoise can be surprisingly fragile and require extra care.
This stone clocks in at a 5 to 6 on the Mohs Hardness Scale, which means it's pretty easy to scratch or damage if you're not careful. Turquoise is also particularly sensitive when it comes to solvents. Perfume, lotion, soap, and even oils from your skin may eat away at the finish and alter the color or quality of your turquoise.
Additionally, you shouldn't wear turquoise for long periods in direct sunlight. Time spent at the beach, park, or sun-bathing may discolor or fade your turquoise, lowering its value.
On the bright side, it's incredibly affordable and easy to buy turquoise jewelry (and replace it if damaged), as you'll learn next.
Like other opaque gems, the price of turquoise dropped significantly when special treatments were introduced and flooded jewelry stores with imitations and synthetics. Even still, untreated, genuine turquoise will always command a higher price and retain its value.
Buying turquoise can be tricky. It's one of the few gemstones not to be evaluated by the 4C's. It's neither clear nor cut. And just like zircon, turquoise is valued and sold based on size, not carat weight.
Color is the biggest predictor of price when buying a turquoise birthstone. Stones closer to robin's egg blue are most valuable. The matrix veining found in turquoise may raise or lower the stone's price, depending on how you or a jeweler feels about it. While some love the distinctive veining, others see it as a blemish on an otherwise cheery stone.
That's why most turquoise is priced according to the Turquoise Quality Index. This scale between 8 and 100 uses eight factors across two categories (structure and rarity) to evaluate each stone's quality and value. The higher the score, the pricier the stone.
Keep these tidbits in mind when you need a fun conversation-starter after someone compliments your turquoise jewelry:
Now let’s meet the final December birthstone, a relative newbie on the gem scene.
All the tanzanite ever found comes from one place: Tanzania.
In 1967, a massive wildfire scorched most of the grass and earth in the Merelani Foothills near Mount Kilimanjaro (the largest free-standing mountain in the world). This revealed a cache of rare, bright blue-violet stones, a result of the fire heat-treating the ancient rocks.
Local livestock herders thought the stones were sapphires because of their blue color. When the government approved mining, experts learned the rocks were a previously unknown zoisite variation believed to have formed during Mount Kilimanjaro's first volcanic eruption 585 million years ago.
Seeing the potential commercial appeal of these highly-saturated, "velvety," lustrous stones, Tiffany & Co. inked a deal to become the gem's official international distributor. The famous jeweler rebranded the zoisite as tanzanite, named after where the birthstones were discovered.
A Tiffany & Co. campaign advertised the glamorous new discovery with images of large-cut, vivid tanzanites boasting high-clarity and sparkle. They caught on like the wildfire that led to its initial discovery.
Tanzanite is a zoisite, which is a group of minerals that occur as prismatic crystals. Zoisites dazzle in all sorts of colors, from green, yellow, and pink to gray and colorless varieties.
A huge reason tanzanite is so popular is because it's never just one color. Tanzanite is pleochroic, which means it reflects different colors when you look at it from different angles.
In its raw state, tanzanite is one of the only birthstones to show off trichroism (aka appearing up to three different colors at once). The stone often has shades of brown, blue, and violet.
However, when tanzanite is heated (either naturally by artificial processes), the brown or burgundy color disappears, and violet-blue colors emerge. This makes the stone "dichroic" as it only reflects two colors: blue and violet.
It's rare to find naturally heat-treated tanzanite as zoisites are usually red, brown, or clear. But simply heat-treating the stone at 600 degrees for less than one hour allows the blue, indigo, and violet tones to come out and dazzle.
Though tanzanite is often confused with sapphire because both stones share a deep blue color, sapphire lacks the violet and indigo tones tanzanite is known and cherished for.
Tanzanite ranks a 6.5 on the Mohs Hardness Scale, so tanzanite jewelry is pretty durable, but can still get scratched during wear and tear. It's also prone to breaking if hit too hard.
Due to its rarity and higher price tag, you're less likely to find tanzanite in casual, everyday jewelry. Unlike the other two December birthstones, tanzanite shines best in fancier fine jewelry and special occasion pieces.
Because tanzanite only forms in one small region, its availability and price are entirely dependent on the supply and events happening there. According to insider studies, current tanzanite production rates may cause one of just four tanzanite mining blocks to deplete its stores before 2042. This means tanzanite may shoot up in price, value, and rarity.
How much does tanzanite cost?
Like diamonds, tanzanite prices increase as you go up in carat weight. The better the stone's clarity, color, and cut, the higher the price.
Deeper blue stones are more valuable than those skewing toward a lavender, violet, or purple-tone majority. Make sure to pay attention to the stone's cut, as some will help emphasize and reflect the blue in the tanzanite gemstone versus the purple.
Lower-quality tanzanites range from $150 to $200 per carat, while high-quality tanzanites may cost $600 to $1,500 per carat. That's why tanzanite is typically set as smaller stones in December birthstone jewelry.
Tanzanite was only discovered in 1967, so it hasn't had time to rack up fantastic myths and lore. But these interesting facts are still worth sharing:
Each piece of birthstone jewelry you wear or gift has a personal and identifying meaning, whether for a birthday, anniversary, or milestone during that month. You can even wear a December birthstone to honor and remember a special person in your life.
No matter which gem you choose, December birthstones offer a range of options: turquoise for a casual everyday look, blue zircon for a touch of extra glam, and tanzanite for fancy occasions and unforgettable gifts.
There’s a perfect December birthstone to match everyone’s individual personality, style, and jewelry-wearing habit. So have fun finding the blue gem that speaks to you!