What's the Most Expensive Diamond Cut?

Diamond cuts naturally affect price -  different diamond cuts will be more expensive, depending on the stone’s design and proportions, and how it interacts with light. Learn more about how the cut of a diamond can affect price and which are the most and least expensive diamond cuts in Australia.

Which Diamond Cut Is the Most Expensive?

The round cut is the most expensive diamond cut. Renowned for its brilliance, the round cut features 58 facets arranged to maximise light reflection. To produce the shape of the round cut, almost 60% of the raw diamond material goes to waste; which naturally makes an expensive cut to produce. 

The classic shape of the round cut is the main reason that it’s the most popular and in-demand cut. It’s estimated that up to 75% of all diamonds sold worldwide are round cut.

How Cut Affects a Diamond

Cut is one of the four key factors that determine a diamond’s price. In the diamond industry, the 4Cs (Colour, Carat, Clarity, and Cut) are the primary factors that determine overall quality and cost. 

Diamond cut is often associated with the shape of the gem. However, a diamond’s cut is also about the specific angles and number of facets of the stone, which affect how the stone reflects light. Shaping, cutting, and polishing raw diamonds involves adding facets to the stone in specific positions to increase overall sparkle.

When evaluating a diamond’s cut, gemologists look at brilliance, dispersion, and scintillation.

• Brilliance refers to the intensity of white light a diamond can produce, affecting how bright it appears. 
• Dispersion, or a diamond’s ‘fire’, appears as colourful streaks when light splits inside the stone.
• Scintillation creates glints of light as a diamond moves or rotates. The more facets a diamond has, the more it will appear to sparkle when moved.

How Diamond Cut is Measured

The Gemological Institute of America (GIA) grades diamond cuts into four categories:

Excellent - the highest grade of cut where little to no light leakage occurs as light passes through the stone. Diamonds with an Excellent cut are priced at a premium. 

Very Good - a diamond cut with minimal light leakage that almost reaches the maximum potential of the stone’s shine. The difference in brilliance between a Very Good and an Excellent cut diamond is nearly indistinguishable to the naked eye. 

Good - Good diamonds have sparkle, though less bright than higher-graded stones. Good cut grading is seen in diamond cuts like Emerald and Asscher, where the style of the stone is favoured over its brilliance. 

Fair/Poor - Diamonds with a Fair or Poor grade have a lot of light leakage and do not reflect light well. Fair and Poor cut diamonds are not recommended for fine jewellery like an engagement ring.

How Diamond Cut Affects Price

A diamond’s price depends heavily on its cut grade. A well cut diamond with a smaller carat weight can be priced higher than a larger diamond with a poor cut.

Excellent cut diamonds can fetch 25-30% more than a similarly weighted and coloured diamond with a Good grade. Conversely, Fair cut diamonds will be much cheaper compared to diamonds at a higher grade.

When purchasing a diamond, it is important to consider its cut grade. A poorly cut diamond may be priced lower, but it may lack brilliance and appear dull.

Types of Diamond Cuts and Prices

Diamonds cut in different styles will also be priced differently -  the differences in price are influenced by market demand and popularity rather than quality. Here’s what you can expect in terms of price for the different diamond cuts, based on 1-carat diamonds graded with a G for colour, VS2 for clarity, and an Excellent cut. 

*Average prices calculated and may vary depending on the retailer and current market. 

The above table offers a general guide to the differences in cost between diamond cuts. The data shows that the round brilliant cut is the most expensive, driven by its popularity for custom engagement rings and wedding rings. 

Buyers looking for a diamond with sparkle similar to the round brilliant can consider the princess cut. A princess cut diamond can cost 30% less than a comparable round cut diamond, while offering a similar brilliance. The princess cut has either 57 or 76 facets, and features square edges. 

Cushion, asscher, and radiant cuts are affordable diamond cuts that offer the benefit of a contemporary style over a traditional round diamond. While not as brilliant, they feature distinctive shapes and facet patterns that are eye-catching in a different way. 

We have a team of in-house diamond experts at our showrooms in Sydney, Melbourne, and Brisbane to help you find the perfect diamond in terms of cut, colour, and clarity for an engagement ring or a special piece of jewellery. Explore our collection of natural diamonds, from timeless round cuts to sleek emerald styles, each handpicked for brilliance and quality. We also have a collection of lab-grown diamonds that offer the same sparkle, clarity, and durability as mined stones.