Hearts and Arrows Diamonds Explained

• IGI-certified diamonds
• Triple Excellent standard
• Lifetime setting upgrades
• Free, fully insured shipping
• Made to order in Toronto

Hearts and arrows is a pattern that appears in a round brilliant diamond cut to near-perfect optical symmetry — eight arrows seen from the top, eight hearts from below. It is not a grade, it does not appear on a GIA or IGI report, and — this is the part most guides skip — it is not the same thing as the Symmetry grade printed on your certificate. Here is what the pattern actually is, how it is formed, what it does and does not tell you, and whether it is worth paying for.

Key takeaways

• Hearts and arrows is a sign of optical symmetry — the three-dimensional alignment of facets.
• It is not a laboratory grade. No major report certifies "hearts and arrows".
• Optical symmetry is not the same as the Symmetry grade on your certificate — that measures something narrower.
• The hearts are an optical illusion; there are no heart-shaped facets on the stone.
• It applies almost exclusively to round brilliants.
• A hearts and arrows stone is very likely well cut — but the pattern alone does not guarantee light performance.

What are hearts and arrows?

Look down through the table of certain round brilliant diamonds under the right viewer and you will see eight arrows radiating outward in a perfectly even starburst. Turn the stone over and look through the pavilion and you will see eight hearts arranged around the culet. The pattern is crisp, symmetrical and unmistakable when it is there — and visibly ragged when it is not.

The pattern was popularised by Japanese cutters in the 1980s as a way of demonstrating cutting precision beyond what grading reports measured at the time. It has since become a trade shorthand for a very precisely cut round brilliant.

How the pattern is formed

There are no heart-shaped or arrow-shaped facets on a diamond. The pattern is entirely a product of reflection — you are seeing facets reflected in other facets, which is why it only appears when the alignment is nearly perfect.

In a standard round brilliant's 57 facets, each heart lobe is created by a pair of lower girdle facets, with the point of the heart formed where those lower girdle facets meet the pavilion main facet. The arrows seen from above are the reflections of the pavilion main facets. For eight clean, identical hearts and eight clean, identical arrows to appear, every one of those facets has to be cut at the same angle, the same length and in the same position as its seven counterparts — in three dimensions.

That is a demanding standard, and it is precisely why the pattern is useful: it is a visual test that reveals misalignment the eye would otherwise miss. A slightly long lower girdle facet, a pavilion main a fraction off angle, and a heart splits or an arrow blurs.

Optical symmetry is not the Symmetry grade

This is the single most misunderstood point, and it is worth getting straight because it explains why a diamond can be graded Excellent for symmetry and still show a messy pattern.

	Symmetry grade (on the report)	Optical symmetry (hearts and arrows)
What it measures	Whether facets meet where they should — meet-point precision, alignment of the table and girdle	Whether all eight-fold facet sets are identical in three dimensions
Who assesses it	The grading laboratory	Nobody officially — it is observed through a viewer
Appears on a certificate	Yes — Excellent to Poor	No
Standard required	Strict	Stricter

In short: optical symmetry is a higher bar than the graded Symmetry line, and it is the stricter one that produces the pattern. Every hearts and arrows stone should grade Excellent in symmetry, but the reverse does not hold — plenty of Excellent-symmetry diamonds show no clean pattern at all. Our guide to symmetry and polish grades covers what the certificate line actually assesses.

How to see hearts and arrows

You cannot see the pattern with the naked eye or through a standard loupe. It requires a hearts and arrows viewer — a simple, inexpensive tube-shaped scope with a coloured reflective cone and a lens, which controls the lighting so the reflections resolve. Arrows are viewed from the crown, hearts from the pavilion, which means the stone must be unmounted or viewed from beneath an open setting.

Two practical cautions. First, images of hearts and arrows are easy to flatter — lighting, angle and even a slightly tilted stone change how crisp the pattern looks, so a supplier's photograph is weaker evidence than it appears. Second, a mounted stone in a closed or bezel setting simply cannot be checked from below, which is one reason the pattern is discussed at the point of buying a loose diamond rather than afterwards.

Does hearts and arrows mean a better diamond?

Usually, but not automatically — and the honest version of this answer is more useful than the marketing one.

What it does tell you: the stone was cut with unusual precision, by a cutter willing to sacrifice weight to hold exacting angles. That is a genuine indicator of craftsmanship, and precisely cut stones tend to perform well.

What it does not tell you: that the diamond returns light optimally. Optical symmetry is about facets being identical to each other — it says nothing about whether those angles are the right angles. A stone can be perfectly symmetrical and still be cut too deep or too shallow, leaking light through the pavilion or showing obstruction. Symmetry and proportion are two different questions, and hearts and arrows only answers the first.

This is why proportions remain the substantive measure. Table and depth and the underlying crown and pavilion angles determine where the light goes; optical symmetry determines how evenly it is organised when it gets there. You want both, and if you can only verify one, verify the proportions — they are printed on the report.

Do fancy shapes have hearts and arrows?

Effectively no. The pattern depends on the eight-fold radial symmetry of the standard round brilliant facet arrangement. Shapes without that structure — oval, cushion, emerald, pear, marquise, radiant — cannot produce it, though some patented cuts create their own signature patterns by other means. If a seller advertises hearts and arrows in a fancy shape, ask precisely what they mean.

For those shapes, cut quality is judged on proportions and the length-to-width ratio instead, along with an eye check for the bow-tie in elongated brilliants.

Is it worth paying a premium for?

Hearts and arrows stones typically carry a premium, because achieving the pattern costs the cutter carat weight and time. Whether that premium is worth it depends on what you value.

If you are buying a round brilliant and precision matters to you as a thing in itself — the same instinct that draws people to well-made watches — it is a reasonable place to spend. If your priority is the largest, best-performing stone for your budget, the premium is better spent on carat weight or held back entirely, because a Triple Excellent round with ideal proportions will already look superb. What you should not do is treat the label as a substitute for reading the report.

The Montare view

Our floor is Triple Excellent — Excellent cut, polish and symmetry — with table and depth held in the ideal range for the specific shape, alongside D–E colour, VVS1–VVS2 clarity, three carats minimum and IGI certification. The per-shape figures are published on our standards.

We do not market hearts and arrows as a headline, because it is not a graded property and we would rather commit to things a report can verify. That preference for legible, verifiable grades is also why we specify IGI: IGI grades lab-grown diamonds on the full 4C scales, while since 1 October 2025 GIA has issued only a two-tier Premium or Standard classification for lab-grown stones — see the 2025 GIA grading change. What we will do is answer the question directly: if optical symmetry matters to you on a round brilliant, say so during your consultation and we will factor it into the search. The process is that you describe what you are looking for and we go and source the stone that meets it — so a preference like this is simply part of the brief. Our goldsmiths then cast, set and polish the ring by hand in Toronto. Start in the ring builder or book a consultation.

Frequently asked questions

What does hearts and arrows mean in a diamond?

It describes a round brilliant cut to near-perfect optical symmetry, which produces eight evenly formed arrows when viewed through the crown and eight hearts when viewed through the pavilion. The pattern is a reflection effect, not physically heart-shaped facets.

Is hearts and arrows a grade on a diamond certificate?

No. Neither GIA nor IGI certifies hearts and arrows. It is a trade observation made through a special viewer, not a graded property, which is why it should never be treated as a substitute for reading the cut, polish and symmetry lines on the report.

Is optical symmetry the same as the Symmetry grade?

No, and this is the most common confusion. The Symmetry grade on a report assesses meet-point precision and alignment. Optical symmetry is a stricter, three-dimensional standard requiring all eight-fold facet sets to be identical. Every hearts and arrows stone should grade Excellent for symmetry, but many Excellent-symmetry stones show no clean pattern.

How do you see hearts and arrows in a diamond?

Through a hearts and arrows viewer — an inexpensive scope with a coloured reflective cone that controls the lighting. Arrows are seen from the top, hearts from underneath, so the stone must be loose or in an open setting. The pattern is not visible to the naked eye or through an ordinary loupe.

Does hearts and arrows mean the diamond sparkles more?

Not necessarily. Optical symmetry means the facets are identical to one another; it does not confirm they are cut at the correct angles. A perfectly symmetrical stone can still be too deep or too shallow and leak light. Proportions determine light return; optical symmetry determines how evenly it is organised.

Can fancy shapes have hearts and arrows?

Effectively no. The pattern relies on the eight-fold radial symmetry of the round brilliant facet arrangement, which oval, cushion, emerald, pear, marquise and radiant cuts do not share. For those shapes, cut quality is judged on proportions and length-to-width ratio.

Are hearts and arrows diamonds worth the premium?

It depends what you value. The premium is real because the pattern costs the cutter weight and time, and it is a genuine sign of precision. But a Triple Excellent round with ideal proportions already performs superbly, so if size or budget matter more, the money is better spent elsewhere.

Do lab-grown diamonds have hearts and arrows?

Yes. The pattern is a function of how a stone is cut, not how it was formed, so a lab-grown round brilliant cut to the same optical symmetry shows the same hearts and arrows as a mined one.

Precision you can read on the report. Build a ring in the ring builder or book a consultation.