< Engagement Rings & Weddings / Engagement Ring Styles
7 Reasons Why
Trillion Cut Diamonds Deserve Your Full Attention
This brilliant geometric diamond cut shines in a wide variety of styles.
If you’re looking for an unusual diamond shape with lots of fire, look no further. The trillion cut diamond, also called trilliant, has a unique triangle shape combined with a brilliant-cut diamond’s flat top and sparkling facets. This combination makes it an excellent choice for people looking for a non-traditional shape who don’t want to sacrifice sparkle.
This under-the-radar cut is gaining popularity among those who want something unique—whether for an engagement ring, earrings, or a modern pendant. With its striking proportions and sculptural flair, these diamonds offer a dramatic, fashion-forward alternative to more traditional diamond shapes without sacrificing brilliance.
Meet the Expert
- Kristen Shirley is a New York-based luxury expert, writer, editor, and stylist who specializes in travel, fashion, fine watches, jewelry, wine and spirits.
- She is the founder of La Patiala, the luxury encyclopedia
- Her work has appeared in Bloomberg Businessweek, Departures, Business Insider, Robb Report, and Editorialist, among others
Ahead, discover the many reasons why trillion cut diamonds are capturing the attention of modern jewelry lovers—and how to wear them in fresh, unforgettable ways.
What Is a Trillion Cut Diamond?
Also known as a trilliant, the trillion cut diamond is a three-sided diamond with either slightly curved or perfectly straight edges. Its name is a clever portmanteau of “triangle” and “brilliant,” referencing both its shape and its faceting style. Like a traditional brilliant cut, this diamond is designed to maximize sparkle, but its angular form and wide table give it a uniquely modern edge.
Trillion cut diamonds can vary slightly in appearance—some are sharply geometric with crisp points, while others feature softly rounded edges for a more organic look. Most trillion cuts are symmetrical, with equal-length sides and a flat top surface that enhances light reflection.
1. There Are Two Types of Trillion Cut Diamonds
While all trillion cut diamonds have a triangular shape with three sides, usually of equal length, there can be slight but significant variations that affect their overall appearance. The sides may be perfectly straight, giving the stone a sharp, modern, and architectural look, or they can be subtly curved, which softens the edges and can make the diamond appear slightly larger face-up. Curved sides also tend to reflect light differently, adding a bit of fluidity and sparkle to the otherwise bold geometry.
2. Trillion Cut Diamonds Make Beautiful Accent Stones
An engagement ring with a central trillion cut diamond is unusual, but many designers feature them as side stones. They add a gorgeous sparkle, and the tapered edges suit most settings. Trillion cut diamonds are especially striking next to square or rectangular stones. This Brent Neale Gypsy ring uses two trillion cut diamonds to flank an emerald-cut diamond. The triangular shape is even more striking when set in yellow gold.
3. Trillion Cut Diamonds Look Bigger Than They Are
Trillion cut diamonds are typically moderate-to-shallow diamonds, so they appear larger than diamonds with a deeper cut because more of the diamond is visible from above. In addition, the long sides can give the appearance of being larger than it is, so a trillion cut diamond is perfect for people who are looking for a big look on a budget.
4. Trillion Cut Diamonds Make Stunning Toi et Moi and Bypass Rings
A Toi et Moi ring combines two stones, one representing you and the other your beloved. Designers use an open setting that curls around the finger in traditional Toi et Moi rings. However, if this setting doesn’t suit your personal style, two trillion cut diamonds make a gorgeous graphic statement, and the design is as unique as your love. KatKim’s Highland ring is a perfect example. It features two 5mm trillion cut diamonds set on both sides of a gold band with pavé diamonds.
This type of design keeps the romantic notion of a Toi et Moi ring but has a minimalist modern look. Designers also use trillions in classic bypass rings, like this one from Lang Antiques.
5. Trillion Cut Diamonds Make Unique Engagement Rings
It’s uncommon to find an engagement ring with a central trillion cut diamond, so you’ll be sure to stand out in the crowd. The geometric shape suits many different settings, including bezels, halos, and solitaires. Some designers find a romantic notion in its shape. Belgian jewelry designer Dries Criel says, “For me, trillions and its three sides represent past-present-future. It’s a reminder of the circle of life and especially the timelessness of fine jewelry and the part it can play in somebody’s life.”
6. You Can Swap Round Diamonds for Trillion Cuts in Modern Jewelry
Anita Ko uses these diamonds in several designs, and the triangular shape completely changes the look of classic styles. In bracelets, she uses them in two different ways. A pavé cuff is even more glamorous with three trillion cut diamonds set among the shimmering stones. Replace round diamonds with trillions in a tennis bracelet or eternity bracelet, and you’ll have a design that’s sure to stop people in their tracks.
7. Trillion Cut Diamonds Are an Excellent Choice for “Floating” Diamond Designs
Designers love to use these diamonds in settings where the diamond appears to float. The flat edge of the triangular shape fits neatly alongside the ring’s band. A hidden setting underneath supports the diamond, but it looks like it’s floating on your finger. KatKim’s Trillion Peak ring and Jemma Wynne’s Bespoke ring are perfect examples. Anita Ko even uses a floating trillion cut diamond to add sparkle to a Cuban link necklace.
Trillion cut diamonds offer a bold, modern alternative to traditional shapes, combining brilliant sparkle with a distinctive silhouette. Whether used as a striking center stone or a sparkling accent, they bring unexpected elegance to any piece of jewelry. With their growing popularity and versatile appeal, these diamonds are a timeless choice for anyone looking to stand out with natural diamonds.
