Which Of The 4 C’s Are The Most Important?

When determining the market value of a diamond and whether it’s worthy of investment, experts use the 4 Cs diamond guide to gauge the resale opportunities. These four elements — cut, clarity, colour and carat — are globally accepted standards for assessing the quality of a diamond, its strengths, best features and, of course, its overall value.

This blog will unpack the most important of the 4 Cs so you can easily determine which aspects are most important when it comes time to expand your portfolio or invest in a precious stone. Though it’s important to invest in expert, external advice, being equipped with how to make informed decisions will stand you in good stead when you’re considering investment opportunities.

The 4 Cs of diamonds in order of importance

  1. Cut

When it comes to the physical beauty of a precious stone, an  important part of the 4 Cs is the cut of the diamond. The number of facets, the angle of facets and the symmetry and alignment of the diamond shape determines its sparkle. It takes decades of training as a stone cutter to bring the best out of a natural diamond. So, if a diamond is poorly cut, no amount of clarity grading, colour grading or carat weight will make up for it. When cut too little, the stone loses facets that capture the light, drastically dimming its sparkle. When cut too much, the value of the stone decreases.

When jewellers discuss the 4 Cs of diamonds, cut also refers to the shape of the diamond itself. Diamonds can come in round shapes, modified shapes (including love hearts) and traditional shapes, such as square cut, cushion or princess cut diamonds, emerald cuts, and pear and marquise shapes.

The science behind diamond cutting makes this aspect the most important of the 4 Cs

Achieving the ideal cut involves a careful combination of art and science. The precision of a cut has the potential to impact the value of a diamond by more than 50% — so this is the most important of the 4 Cs to consider when purchasing precious stones for your investment portfolio. Even the best gemologists take considerable time to study the rough diamond before they even contemplate picking up a tool. As they assess the stone, they consider its grains, noticeable flaws, and precise measurements to ensure they can give the diamond the premium symmetry, polish, and proportion needed to shine.

Crucial factors to consider when choosing a diamond cut:

  • Symmetry — The best diamonds are symmetrical, meaning the facets on any of their sides are similar to the facets facing them across the diamond’s axis. Nowadays, a well-cut round diamond has 58 facets with a culet and 57 facets without a culet.
  • Proportions — A diamond’s proportions are based on Tolkowsky’s ideal diamond design. Tolkowsky used the diamond’s diameter to conclude that for optimal light reflection, the total depth of the gem should be 59.3% of the diameter. The diamond’s table should not measure beyond 53% of the diameter, and the height of the diamond crown should be 16.2% of the diameter. Additionally, the diamond should always have a pavilion depth of 40.75 degrees.
  • Polish — Given the diamond picks up minor surface blemishes when it’s cut, the final step of the process is polishing. Diamonds are polished with diamond dust and other abrasive materials to smooth the surface so the light can enter and exit the gem seamlessly.


  1. Colour

When it comes to the 4 Cs of diamonds and their order of importance, colour is the most significant factor to consider in an Argyle diamond. The colour of a gem refers to the natural tint within a diamond, and even the most subtle and minute differences can dramatically impact the stone’s value.

That’s why diamonds are assessed under controlled lighting and viewing conditions before being separated into three categories — hue, saturation and tone. The hue refers to the dominant colour of the stone, which may also come with a tint or subtle undertones of another shade. Saturation describes the vividness with which the colour is present and can rate from light to intense according to the strength of the saturation. Tone refers to how light or dark the colour in the gem appears to be. The stronger the colour in the diamond, the rarer it is. That’s why a diamond with a colour grading scale of 1 to 6P PP or PR is considered the ideal choice and a tremendous investment. The scale extends from 1 saturation grade being the best quality to 9 saturation grade being the “lightest”.

  1. Clarity

When assessing the 4 Cs of a diamond, the clarity is determined by carefully examining any exterior or interior imperfections that the naked eye cannot see. Blemishes on the surface of the stone and flaws in its inclusions are taken into account when rating the stone’s clarity under a magnified microscope. If a diamond has minimal inclusions and blemishes, it will have a greater clarity grade, increasing the stone’s monetary value.

When using the Argyle diamond clarity chart, the scale ranges from I (meaning “included”) to FL (“flawless”, with no internal or external imperfections). Within this scale there are subgrades that provide further information about the visibility of the inclusions. While determining the clarity is essential, most tend to spend their budget on aspects of the diamond they can see with the naked eye — such as colour and cut.

When it comes to Argyle coloured diamonds, as long as the diamond eye is clean, the saturation and hue of the tint will win out over pure clarity when it comes to more valuable pieces. 

  1. Carat

When we assess the 4 Cs of diamonds and their order of importance, carat is the final factor to consider — but one that shouldn’t cloud your judgement. Carat is the measurement of weight used to describe diamonds. One carat is equivalent to 200 milligrams, and each carat measure is subdivided into a further 100 points to allow for highly accurate grading of the weight of each stone.

It’s important to note that carat should not be confused with size. The stone’s density and cut often impact its weight, so two diamonds of the same carat count will almost inevitably vary in size and shape. This is why it’s the least important of the 4 Cs of diamonds. Fancy and bold shapes like ovals, rectangles and marquises tend to look larger for their carat weight, while a ring with a narrow band and a halo setting can create the illusion of a bigger diamond.

Argyle Diamond Investments can help you find your diamond’s 4 Cs

While the cut is important of the 4 Cs, colour, clarity, and carat also combine to create a premium grading scale that experts use to determine a jewel’s overall character and quality. These factors give the stone its sparkle, shine and unique characteristics that ultimately determine its value in the diamond market. 

Here at Argyle Diamond Investments, we understand a valuable stone and can gauge what combination will result in solid profitability for investors. As Australia’s premium wholesaler of rare pink, red and Argyle blue diamonds, we pride ourselves on connecting our clients with rare gems that ensure a quality return on investment. From acquiring and managing your diamond investment to reselling your gem to a competitive buyer, get in touch with us today about investing in the lucrative diamond market. Alternatively, organise a VIP diamond viewing to talk to us in person.

Argyle Diamond Investments Pty Ltd are Australia’s largest supplier of Australian certified pink diamonds and have exclusive use of the Australian Pink Diamond Analytics program. This program is a data driven decision maker that tracks and statistically analyses the rarity, financial growth and value of all investment grade pink and blue diamonds. With this valuable information, Argyle Diamond Investments Pty Ltd can offer all clients an investment grade pink from $5,000AUD up. But, the highest growth diamonds, are the larger, stronger colour pinks starting from around $20,000AUD plus.


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