The Heart Cut Diamond

This rare and complex cut is all about balance.

Intrinsically linked to love and romance, the heart-shaped diamond naturally lends itself to sentimental pieces of jewellery, the most popular of these, of course, being an engagement ring. While it remains an unusual choice for jewellery, it is this very fact that sees buyers searching for the best heart-cut diamond.



A heart-shaped diamond stands out from the crowd with its symbolic beauty and soft symmetry.

Like any other cut of diamond, the performance of a heart shape is dependent upon the cut, colour, and clarity of the stone, and an understanding of these will ensure you get the best possible diamond for the most reasonable price.

The heart is the most difficult of all diamond shapes to cut and combined with the lack of demand for this shape, finding a good quality, well-priced heart diamond might be a real labour of love. Although there is no set cut grading scale for heart-shaped diamonds like there is with brilliant round diamonds, there are a couple of things to look out for to make sure that you get a great looking stone.

Length to Width Ratio

The ideal length to width ratio for a heart-shaped diamond is 1.00, meaning a diamond is precisely as long as it is wide.

Heart-shaped diamonds with a perfect or near-ideal length to width ratio will look proportionate and natural, without appearing overly bulbous or stretched.

Diamonds of this cut with a ratio of less than 0.90 will look “chubby” and overly wide.

Diamonds of this cut with a ratio of 1.10 or above often look stretched, elongated, and excessively thin.

For the optimal appearance, we recommend choosing a heart-shaped diamond with a length to width ratio as close to 1.00 as possible. Diamonds of this cut within the 0.90 to 1.10 range can also look fantastic, depending on your personal preferences.

Symmetry is graded on a scale from poor to excellent, and you should go for as high symmetrical grading as possible to ensure that the stone has a consistent outline and is not lopsided. Each of the rounded lobes should be an equal-sized and semi-circular, with no straight lines, and the indent between them should be directly in-line with the pointed tip.


Depth Percentage & Table

Depth percentage is the ratio of the depth to the width of the heart-shaped diamonds. “The depth is an excellent cut,” is what you want to hear when a consultant offers a heart diamond to you. The depth, as seen below, plays an important role in the diamond’s shine.


The size of the table concerning the rest of the stone is important because the table is where the majority of light enters the stone. This needs to be carefully balanced with the other proportions to ensure that the correct amount of light enters the stone to allow for maximum sparkle. A larger table is not always better.


Carat Weight

The relationship between a diamond’s carat weight and its visible size is not always a direct one. When we judge a diamond’s size, we look at it from the top – known as the ‘face-up’ position in the jewellery trade. However, much of the weight of a diamond is actually carried on the bottom half of the stone, where it cannot be seen.

With fancy cuts like heart-shaped diamonds, the shape of the diamond becomes more visually appealing at larger carat weights. The higher the carat weight of the diamond, the more visible and apparent the heart shape becomes. We generally recommend choosing a heart-shaped diamond in the 1+ carat range.

A diamond of this size looks distinctly heart-shaped, whereas the heart shape of a smaller diamond can be harder to see once it’s set in a ring.

To imagine how some of the carat weights look, we compared them to something we all are familiar with – a 10 cent coin.


If you have a limited budget, aim for 0.5 carat as absolute minimum carat weight. Below this point, it becomes increasingly difficult to notice the unique heart shape of this diamond cut.

Ultimately, the ideal carat weight for a heart-shaped diamond depends on your taste and budget. If you need help choosing the right diamond, contact our sales team who will help you get the largest, highest quality diamond for your budget.

The diamond colour grades used by the GIA range from “D” to “Z”.  A “D” grade indicates that a diamond is colourless. At the other end of the scale, a Z grade identifies a diamond with a clearly visible yellow or brown tint.

Heart-shaped diamonds are a modified version of the brilliant round cut. As they reflect lots of light, the colour of a heart-shaped diamond is harder to distinguish than it is in a diamond with a large table, such as an emerald or Asscher cut. This means that there’s no need to choose a flawless colour grade.

Doing so will only increase the price you pay for the diamond, without having any noticeable impact on how it looks when viewed with the naked eye.


Colour Grade

At the rounded end, the stone should give off great sparkle due to the brilliant-cut facets reflecting light back to your eye. This is great because it can distract and hide minor imperfections and a lower colour grade. However, as with other stones that end in a point (marquise, pear, etc.), the heart shape is more likely to show a concentration of colour at the tip of the stone, and this area won’t have the sparkle to hide it.

When it comes to heart-shaped diamonds, there’s no one-size-fits-all colour grade that offers the best value for money. Instead, it’s best to pick a colour grade based on the type of metal you plan to use for the diamond’s setting. For a white gold or platinum setting, we generally recommend choosing a diamond that has a colour grade of H or better.

Bow-tie Effect



The “bow-tie” effect is a phenomenon that affects many fancy-cut diamond shapes, including the heart-shaped diamond. It appears as a black shadow pattern across the diamond that resembles the formation of a bowtie.

It is a result of light obstruction and facets that are unable to ‘bounce’ light back towards the eye, causing the dark or black shadows to appear.

Reducing the “bowtie” effect requires a skilled cutter who has carefully considered the angles and proportions involved in all of the diamond, not merely those which may display the bowtie effect.



Certified Stones

The priority that you place on diamond carat weight and how big you want to go is totally up to you. Finding a large heart-shaped diamond (say, over 2 carats), that has excellent sparkle can be tough though, as most high-quality stones of these sizes are used to make other shapes.

When looking at any diamond, you need to ensure that it’s a ‘cert stone’, which means that it has been assessed, graded, and coded with a laser by an independent lab. The lab to trust and to look for certification from is the non-profit Gemological Institute of America (GIA). It’s the most internationally recognized and generally seen as the most impartial of all of the gem labs. Each GIA certificate has a unique report number and detailed information about the stone, covering the four Cs, the height, depth, and other info.

The reason that the GIA is so well respected is that most other labs are part of trade bodies that include jewellery retailers, or are ‘for profit’. While the GIA is very consistent with its gradings, the others have a reputation for being overly generous. What the GIA says is merely a diamond with a ‘good’ cut might be graded as ‘excellent’ by another lab, with an excellent, large price to match.

Diamond certificates are what makes buying online safe and the best way to get a fantastic diamond at the lowest price. Knowing that each diamond you’re considering has been measured and graded by independent experts allows you to make an informed decision.

You can take your time to consider the differences between diamonds and make sure you choose what experts have graded as the best stone, meaning that you get your perfect engagement ring at the best possible price.


Heart Cut Facets 

A heart-shaped diamond typically has 56 to 58 facets, with six to eight facets making up the diamond’s pavilion. Cut to a high level of quality; a heart-shaped diamond can have stunning brilliance, as well as an eye-catching shape that symbolizes the shared love between you and your partner. Unique and beautiful, a heart-shaped diamond is a perfect way to show your love for your significant other.

As the heart shape uses a large percentage of the rough diamond, it’s also a more cost-effective choice than a round brilliant cut diamond. Like with any other diamond, it is essential to choose carefully to get the highest quality stone without spending more than you should. If you need help selecting a heart-shaped diamond, contact us, and we will help you find a diamond that matches your tastes and budget