“Antique stones offer character that you can’t replicate.”

Taylor Swift and Travis Kelce are engaged — and the pop star is showing off a diamond big enough to rival one of her new fiancé’s three Super Bowl rings.

According to Vogue, Kelce worked with jeweler Kindred Lubeck of Artifex Fine Jewelry on the ring. Fans (14 million and counting have liked the couple’s engagement announcement on Instagram) and jewelry aficionados are already buzzing about the new bling.

“Taylor’s stone appears to be an antique elongated cushion, somewhere between eight to 10 carats,” New York City-based jeweler Stephanie Gottlieb tells Yahoo. She estimates that a natural diamond of this size could range anywhere between $400,000 and $800,000. “Antique stones offer character that you can’t replicate,” Gottlieb adds.

So, like Swift, it’s one of a kind. It’s also right on trend.

“A super-elongated, antique cushion old mine cut is the trendiest, most requested cut of the moment,” says Olivia Landau, founder of the Clear Cut. “This is something that’s been trending for the past year or so and has become extremely popular, although it’s very, very rare and hard to find.”

The antique nature of the diamond aligns well with Swift’s vintage-leaning style, says Landau. She points out that natural diamonds of this cut have character and charm that stand out from the lab-grown diamonds many brides are sporting of late. “With the rise of the lab-grown diamond, and everything being kind of standardized and perfect. We’ve been seeing more people looking for that uniqueness and almost imperfect vintage feel,” she says.

The rich yellow gold band holding the stone also sets it apart. “Thicker bands and chunkier gold are definitely more statement-making than the traditional dainty solitaire [rings],” says Landau. Megan Kothari of Aaryah agrees, noting the ring’s “delicate hand-engraving, filigree work and potentially some smaller pavé diamonds.”

Indeed, Lubeck’s work features intricate band details. Bezel settings are also a mainstay of her jewelry.

“Swift has a setback bezel,” Landau notes. “It gives it that kind of vintage feel and complements the antique center stone without being a full bezel or button-back Georgian style. It’s very indicative of her aesthetic and style.”

While Gottlieb and Kothari both estimate the diamond being around eight to 10 carats, Landau isn’t so sure.

“It’s not only very elongated, but it’s a little bit of a shallow stone as you can see from some windowing from the inside. So I think it appears a bit larger than its actual carat weight,” she says. “I think it’s probably closer to five, six or maybe seven carats maximum.”

Whatever the size, Landau says it will be nearly impossible to replicate. “I’m honestly nervous,” she says, referring to the calls and client requests she predicts she’ll get following Swift’s ring reveal. “These diamonds are already so sought after and so hard to come by. We’re definitely going to see a huge spike in demand for them and prices going up. … It’s going to be quite challenging.”