Collection: Trilliant Cut Diamonds

A trilliant is a triangular brilliant, usually with three equal sides and either sharp or slightly rounded corners. Some are cut with curved sides for a softer outline, others with straight sides for a sharper, more geometric look. It is a shallow cut relative to its spread, which means it faces up large for its weight. You will also see it called a trillion or trilliant cut — same stone.

Both, but side stones far more often. A pair of trilliants either side of a centre diamond is one of the most enduring three stone arrangements — the triangular outline leads the eye inward and gives the ring a strong, wide shoulder line. They suit a round, oval, emerald or cushion centre particularly well.

As a solitaire a trilliant is a genuinely bold choice. It reads as modern and architectural, and it is rare enough that most people will not have seen one. It needs a setting that protects all three points, and it wants to be a decent size to carry the shape.

Yes, and it matters more than people expect. Two side stones need to agree on outline, depth, colour and clarity, or the eye picks up the difference immediately — one looking slightly warmer or fractionally larger throws the whole ring off balance. They also need to be cut to sit correctly against your particular centre stone.

Finding a genuinely matched pair takes some searching. It is a real part of the work, and it is why buying two trilliants separately from a marketplace rarely produces a good result.

They are the classic partner for a sapphire, emerald or ruby centre, and it comes down to contrast.

A coloured gemstone holds its colour deep in the stone. Put a bright, shallow, white trilliant either side and the diamond throws light outward while the gemstone holds it in — the two behave in opposite ways, and each makes the other more obvious. A blue sapphire flanked by trilliants reads bluer than the same sapphire flanked by rounds, because the flat white planes of the triangles give the eye a clean reference point.

The straight edges help too. A trilliant sits flush against a cushion, oval or emerald cut gemstone without a gap, so the three stones read as one design rather than three things on a band. Rounds leave small spaces; triangles do not.

It is an arrangement that works particularly well in yellow gold, and it is one of the most requested designs we make. We hold natural sapphires, emeralds and rubies alongside the diamonds, so the centre stone and the pair can be chosen together and matched properly for depth and tone.

Three stone is where trilliants belong. A matched pair either side of a centre stone, set close so the triangular outlines lead into it — clean, wide, and one of the most flattering arrangements on the hand.

Solitaire for a trilliant centre, set with V-prongs or a bezel protecting the three points. Bold, contemporary, and genuinely unusual.

Side stones with pavé — a trilliant pair sitting against the centre with small rounds running down the shoulders behind them, which softens the transition into the band.

All made to order in our own workshop, built around your stones.

Very well, and it is an underrated use for the shape.

A single trilliant hangs beautifully — the point at the bottom gives a pendant a natural drop and a defined shape, where a round tends to just sit. Set point-down it reads as elegant and slightly deco; point-up it is more modern and unusual.

A trilliant can also be set into the bail itself, so the top of the pendant carries a diamond rather than a plain loop of metal. Or set just above the main stone with the point aimed down toward it, which draws the eye straight into the centre diamond or gemstone below. Both are small details that lift a pendant considerably.

Because a trilliant faces up large for its weight, it also gives real visible size without the cost of a heavier stone.

The three points want protecting in a pendant just as in a ring, so a bezel or partial bezel is usually the sensible choice.

Three points, and all three need protecting. It is straightforward with the right setting — V-prongs over each corner, or a bezel or partial bezel, both work well. As side stones they are usually set snug against the centre stone and into the shoulders, which protects them naturally. Set properly, they wear perfectly well.

Because there is no cut grade to fall back on. GIA assigns a formal cut grade only to round brilliants, so on a fancy shape the certificate tells you polish and symmetry and little else about how the stone actually performs. Symmetry becomes the closest thing you have to a proxy.

But there are two kinds, and the certificate only covers one. The graded symmetry measures facet alignment under magnification. What you actually see is outline symmetry — whether the two halves mirror each other. A pear with shoulders of different heights, an oval with one end fuller than the other, a marquise with points that do not line up: none of that necessarily drops the grade, and all of it is obvious once the stone is on your finger.

Asymmetry also affects light. Facets that do not align properly send light out the side instead of back to your eye, which is what causes dead patches and heavy bowties.

So on a fancy shape, look for Very Good or better on the certificate — then look at the stone. The outline either reads as balanced or it does not, and that judgement is one you can make yourself in a few seconds.

More readily than in a deeper shape. Trilliants are shallow, so there is less depth of faceting to break light up and hide things — an inclusion has fewer places to disappear into. VS2 or better is the sensible range, particularly for a centre stone. As small side stones it matters less, but they should still be eye-clean against the centre diamond.

The shallow cut also means colour shows a little more readily. For side stones, the important thing is not the grade itself but that it matches the centre stone — a G centre with H side stones will look slightly off, even if nobody can name why. We match them against the centre rather than to a number.

Roughly 7.0 x 7.0 x 7.0mm across the three sides, which is a large face-up size for the weight — trilliants spread more than almost any shape. That is part of the appeal: they give visible presence without carrying the weight, which is exactly what you want in a side stone.

Because our images and videos are taken at high magnification — far closer than any human eye gets to a diamond, and far closer than the standard the stone was graded to.

Clarity grading is done under 10x magnification. That is the international standard: a grader with a 10x loupe decides whether an inclusion is there and how it affects the grade. Online photography routinely runs at twenty, thirty times life size or more, so you are seeing the stone at several times the magnification GIA used to grade it. An inclusion that fills your screen may be something the grader needed a loupe to find at all.

Colour matters too. A white or transparent inclusion — a feather, a cloud, a crystal without body colour — is far harder to see than a dark carbon spot of the same size, because there is little contrast against the diamond around it. Two stones can carry the same grade and look entirely different in the hand for that reason alone.

We photograph at high magnification deliberately. We would rather show you everything than shoot a diamond flatteringly and have you surprised later. But an inclusion that looks obvious on screen is very often invisible in the hand, at arm's length, on a moving finger, in ordinary light.

The grade tells you what is there. The magnification tells you where. Neither tells you whether you would ever notice it — that is a judgement we make face-up, under proper light, on every stone we hold.

Considerably, and it is worth knowing before you compare stones in different places.

Jewellery displays are lit to sell. Rows of halogen or bright LED spots directly above the case flood the stone with intense, concentrated light from every angle. That produces maximum sparkle and, at the same time, washes out inclusions — the scintillation is so busy that small imperfections simply disappear into it. A diamond in a well-lit display case is showing you close to the best it will ever look.

Daylight is the opposite. Soft, diffuse, coming from one direction. Sparkle is quieter, and anything inside the stone has nowhere to hide. Diamond grading uses controlled, colour-balanced daylight-equivalent lighting for exactly that reason — it is neutral, and it is reproducible.

Neither light is dishonest. But if you look at a stone under spotlights and then take it outside, you will see a different diamond, and most of a ring's life is spent in ordinary light.

When you view diamonds with us, you see them under professional diamond grading lights — the same neutral, colour-balanced lighting the laboratories use — and in natural daylight. No spotlit display case. If a stone looks right under those conditions, it will look right anywhere.

Always, and we would insist on it.

A single diamond on its own looks excellent. There is nothing to measure it against, so your eye accepts it. Put a second stone beside it and differences appear immediately that you would never have seen alone — one reads slightly warmer, one has more life, one throws broader flashes while the other glitters more finely.

This is how the trade buys, and it is the only reliable way to judge colour in particular. Colour grading is comparative by definition: graders work against a set of masterstones, not from memory. Your eye works the same way. Two stones a grade apart are obvious side by side and almost impossible to separate one at a time.

So we will put several in front of you. Sometimes that means you choose a lower grade than you came in for because you genuinely prefer how it looks, and sometimes it means you spend a little more because you can finally see the difference. Either way you will know why, which is the point.

No. Every diamond we sell is a natural diamond, and we've never dealt in lab-grown, simulants or treated stones.

A lab-grown stone is a manufactured product. It's grown in a reactor over a few weeks, then mass produced in unlimited quantities in any size or grade. That's the fundamental difference: a natural diamond took billions of years to form and exists in finite supply, while a laboratory-grown one is a commodity with no ceiling on production. It shows in the pricing — as capacity has scaled, lab-grown prices have fallen steeply and continue to fall, and there is no established secondary market for them.

What you're buying with a natural diamond is scarcity and origin. Rare, and natural. It's why we've never sold anything else. Read our full comparison of natural and lab-grown diamonds.

Our diamonds are independently certified, most commonly by GIA, with others graded by DCLA or HRD. The certificate is issued by the laboratory, not by us, and it accompanies the stone when it ships.

Yes. We are in Sydney's CBD and we see clients by appointment, so you can view stones side by side and compare them in person before deciding.

Just ask us. Finding a particular stone is a large part of what we do, and there's no obligation when you enquire. We'll do our best to source the finest quality natural diamond for you.

Our list is smaller than you'll see on some sites, and that's deliberate. Every diamond here is one we've looked at properly before listing it. Many diamond websites show tens or hundreds of thousands of stones drawn from shared trade lists — diamonds held elsewhere that the seller hasn't seen and won't see unless you order one. It looks like more choice, but nobody has assessed the individual stone, and two diamonds with the same details on paper can look quite different.

So if what you want isn't here, tell us what you're after and what you'd like to spend. We'll look for it, check anything we find ourselves, and only show you stones we'd be happy to recommend. If we can't find the right thing at your budget, we'll say so and talk through the options — sometimes a small change in colour, clarity or size makes all the difference.

Either way, you'll only ever be offered a diamond that we have complete confidence in recommending to you, and it will not just be based on the cheapest price.

Yes. Most clients select the diamond first and then the setting — either one of our existing designs or a fully custom piece made to your description or an image. Everything is handmade by our own jewellers.

Yes. We have many loyal customers all over Australia, and we're able to consult by phone and share photos and videos whenever possible.

Distance is not the obstacle people expect. We'll guide you through the options and select the finest quality diamonds and gemstones for you, so you can make an informed decision from wherever you are. The same applies to custom made engagement rings and jewellery — we'll talk you through it and keep you across it as it's made.

We deliver fully insured anywhere in Australia — every capital city, and regional and rural addresses just the same.

If you are able to come in, we'd always rather show you the stones in person — and if you're travelling to Sydney, appointments can be arranged on weekends.

Tell us what you are setting them against and we will match to it. For a pair, matching matters more than pushing the grade — two well-matched H stones will look better flanking your centre diamond than a mismatched G and F. If you want a trilliant as a centre stone, tell us and we will look for one worth the shape. We are a diamond merchant, not a retail jeweller — we do not charge retail prices, and we source natural certified diamonds to suit your budget. Diamond Imports is a foundation member of the Diamond Dealers Club of Australia, and you will deal directly with Daniel throughout.