Trilogy & Three Stone Engagement Rings

A three stone engagement ring, also called a trilogy engagement ring, a 3 stone ring or a three diamond ring, sets three diamonds or gemstones in a row, with the centre stone larger than the two side stones. The side stones usually run at about 60 to 75 per cent of the centre carat weight, which is what gives the trilogy its balanced, tapered profile. The stones can all match in shape, or the side stones can be a different shape that complements the centre, like pear sides with an oval centre, or tapered baguette sides with an emerald cut.

A trilogy suits anyone who wants more presence than a solitaire but prefers a classic, symmetrical design over a halo. The three stone format also works well if the past, present and future meaning speaks to you, if you want to set coloured side stones like sapphires or emeralds beside a diamond centre, or if you simply like the heavier, more traditional feel of a three diamond ring.

Round brilliants with round sides feel classic, while an oval centre with pear sides flows naturally and is one of the most searched three stone styles. An emerald cut with tapered baguette sides nods to Art Deco and remains a popular trilogy layout, and a cushion cut with smaller cushion sides feels softer and more vintage. A princess cut trio is the one to look at if you want sharp, modern lines.

A classic trilogy uses matching shapes, like three round brilliants or three emerald cuts, while a mixed shape design feels more contemporary, with an oval centre and pear-shaped sides, or an emerald cut centre and tapered baguettes. A three stone halo adds a small halo around the centre for extra sparkle, and coloured gemstone side stones in sapphire, ruby or emerald give the ring a more personal feel. A three stone yellow gold ring with diamond sides leans the whole look more vintage.

A contoured wedding band that follows the profile of the three stones gives the flushest fit, and how a three stone ring stacks with a wedding band is one of the most asked-about questions in trilogy designs. A straight band worn with a small intentional gap can also look right, especially with a tapered trio, and a trilogy is substantial enough to wear on its own if you prefer. Whichever way you go, keep the band width proportional to the stones so the trio still reads as the focus.

A trilogy usually costs 30 to 50 per cent more than a solitaire with the same centre stone, because of the two extra stones and the more complex three stone setting. You can offset some of that by choosing a slightly smaller centre, since the side stones add their own spread. Lab-grown stones for the trio keep the price accessible, which is why a lab-grown three stone diamond ring, or a three stone moissanite ring, delivers the look at a sensible price.

Trilogy rings have been popular since the Victorian era, when three stone designs first became tied to sentimental, symbolic jewellery, and the past, present and future framing was then widely marketed by De Beers in the late 20th century. Meghan Markle's original engagement ring, a cushion cut centre flanked by two round diamonds from Princess Diana's collection, brought trilogy rings back into the spotlight in 2017 and helped drive the revival we are still in.