Trillion Cut Diamonds: Everything You Need To Know

Trillion Cut Diamonds – Basics

When properly proportioned, triangular trillion cut diamonds can be stunning as the centerpiece in an engagement ring.

PriceScope Pointer: Most laboratories issue NO CUT GRADE for shapes other than round: If the cut is described as “Ideal” or “Excellent” (etc.) it’s a seller’s description, not a laboratory judgment.

Before going on: Check out the PriceScope Diamond Buying Guide

Trillion Cut Diamond Described

Among the various diamond shapes the trillion cut diamond, also known as the triangular brilliant or trilliant, is a bright and lively cut. Trillion diamonds work well as side stones to accentuate a variety of diamond shapes but can also look spectacular as a solitaire. Like its cousin the heart diamond, trillion diamonds are typically shallow and are often cut from flattened, triangular rough called macles. Trillion cut diamonds are often seen as side stones for other diamond shapes as their shape serves to draw the eye to the center.

Trillion cut diamond

The Fancy, Inconvenient Truth

Many trillion cut diamonds are cut for heavier weight, at the expense of beauty. This is because many grading laboratories, including GIA, do not assess the optical performance of trillion cut diamonds or other fancy shapes. With no standards enforced, manufacturers tend to plan for the highest yield possible.


The AGS and GCAL assess and grade the optical performance of certain fancy shapes. If you’re seeking cut quality affirmation, fancy shapes with performance deficits will not earn the highest marks from those top-tier laboratories.


Trillion Cut Diamond Selection Tips

Durability Caution:

Durability is a concern with trillion cut diamonds’ pointed corners. Typically, trillion diamonds are set with “V-prongs” covering and protecting them.

Length to Width Ratio:

As with its cousin, the heart shape, a ratio between 1.0 and 1.1 is most desirable for trillion cut diamonds.

Other Notes:

Trillion cut diamonds have a shallow profile. The perfect proportions will yield a good face-up size, but a trillion that has been cut too shallow will lack brilliance. Color can also become more visible in trillion cut diamonds because of that shallow profile.

Trillion cut diamonds are good at concealing inclusions.

Traditional trillion cut diamonds come to three very sharp points, while other triangular brilliants may have softer and slightly rounded points.

Trillion cut diamonds look nicely large for their carat weights because they are shallow.

Trillion Cut Diamond Prices

PriceScope has been maintaining trillion cut diamond prices chart since 2017 and you can visit trillion cut diamond prices for the latest retail trillion cut diamond price statistics.

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