What's The Most Expensive Cut Diamond

Diamonds Are a Girl’s Best Friend… and a Bank Account’s Worst Nightmare

Let’s talk about the sparkly rocks that make grown adults gasp and reach for their credit cards. You’ve heard of the Hope Diamond, the Koh-i-Noor, and maybe even the Pink Star. But what if I told you the most expensive cut diamond isn’t just one stone—it’s a tiny, blinding sun that costs more than a private island? Buckle up, because we’re about to dive into a world where a single carat can cost more than a luxury sports car.

The Reigning Champion: The “Pink Star”

Meet the Pink Star, a 59.60-carat oval diamond that sold for a jaw-dropping $71.2 million at auction in 2017. That’s not a typo—seventy-one million dollars for something you could technically hide in your pocket (if you had a pocket made of titanium and a security team of ninjas). Why so pricey? Because it’s an Internally Flawless fancy vivid pink, which is like winning the geological lottery twice in the same week.

For context, that money could buy you 1,000 average American homes, or 14 million cheeseburgers, or one very awkward family reunion with everyone you’ve ever met. But instead, someone bought a pink pebble. And honestly? I respect the hustle.

Why Is the Cut So Important?

Here’s the kicker: a diamond’s cut isn’t about shape—it’s about how light dances inside the stone. A brilliant cut with perfect angles makes the diamond explode with fire, while a lazy cut makes it look like a dull ice cube. The Pink Star has an oval brilliant cut, which maximizes sparkle and makes the pink color look like liquid sunset.

Imagine buying a giant chocolate bar but leaving it in the sun—mushy, sad, and worthless. A bad cut does that to a diamond. But a master cutter can take a rough rock and turn it into a disco ball for your finger. That’s why the cut can account for up to 50% of the price, even more than size or color.

The Runners-Up (Still Rich Enough to Buy You)

If the Pink Star is the queen, then the Oppenheimer Blue is the moody princess—a 14.62-carat vivid blue that sold for $57.5 million. Blue diamonds are rarer than pink ones, but this one’s cut (a cushion shape) is so precise that it looks like a frozen ocean. Then there’s the CTF Pink Star (a cousin of the first) that sold for $71.2 million again, but in a different year. Yes, same price. The market is weird.

But here’s the fun part: the most expensive isn’t always the biggest. A tiny, perfect 1-carat red diamond—like the Moussaieff Red—can cost more per carat than the Pink Star. That little guy is only 5.11 carats but worth over $20 million, making it the priciest per-carat diamond on Earth. That’s like paying $4 million for a single peanut. But it’s a shiny, red, impossible peanut.

What About the “Cut” vs. “Shape” Confusion?

Most people think “round” is a cut, but no—that’s a shape. The cut refers to the quality of the polish, symmetry, and proportions. A round brilliant is the most popular shape, but a princess cut (square) or emerald cut (step-like) can be just as fancy if done right. The Pink Star’s oval cut is actually a modified brilliant, which means every single facet works overtime to bounce light back at your eyeballs.

Think of it like pizza. You can have a round pizza, a square pizza, or a heart-shaped pizza, but if the dough is raw, it’s garbage. Same with diamonds—shape is fun, but cut is everything.

So, What’s the Real Answer?

The most expensive cut diamond ever sold is the Pink Star, period. But the most expensive per carat is the Moussaieff Red—it’s so rare that only a handful of red diamonds exist on the planet. And if you’re feeling extra, the Hope Diamond (a 45.52-carat blue) is valued at $250 million, but it’s not for sale—it lives in a museum with a security system that makes Fort Knox look like a lemonade stand.

So, unless you’re a billionaire with a secret lair, don’t stress about owning one. Instead, grab a glass of fizzy water, look at a piece of cut glass from IKEA, and remember: sparkle is free, even if the diamond isn’t.

The best thing about diamonds? They remind us that patience and pressure can create something blindingly beautiful. And that, my friends, is priceless.