Diamond Buying Guide

Your comprehensive resource for understanding the nuances of diamond selection.
Gain insights into the critical aspects that influence a diamond’s quality and worth.


About Diamonds

Diamonds are among the most coveted gemstones in the world, renowned for their unparalleled brilliance, durability, and symbolic significance.

The 4Cs – Carat, Cut, Colour, and Clarity – are the fundamental criteria used to evaluate the quality and value of a diamond. Here’s what you need to know.



Carat weight measures the size of a diamond, with one carat equivalent to 200 milligrams.

The carat weight of a diamond significantly influences its price, as larger diamonds are rarer and thus more valuable. However, carat weight is not the sole determinant of a diamond’s value or appearance. A smaller diamond with excellent cut, color, and clarity can be more visually stunning than a larger diamond with lesser quality in these areas. When choosing a carat weight, consider the balance between size and the other quality factors to find the best diamond for your needs and budget.



The cut of a diamond is crucial as it directly affects the diamond’s brilliance and sparkle.

A well-cut diamond will reflect light beautifully, creating maximum brightness and fire. The quality of the cut is determined by the diamond’s proportions, symmetry, and polish. Diamonds are graded from Excellent to Poor based on these factors. A superior cut can make a diamond appear larger and more vibrant than a poorly cut stone of the same carat weight. Investing in a high-quality cut ensures that your diamond will have exceptional brilliance and visual appeal.



Diamond colour is graded on a scale from D (colourless) to Z (light yellow or brown).

Colourless diamonds are the most prized as they allow the most light to pass through, enhancing their sparkle. As you move down the scale, the presence of colour becomes more noticeable, and diamonds may appear less brilliant. However, some diamonds, known as fancy coloured diamonds, are valued for their unique and vibrant hues. When selecting a diamond, consider your personal preference and the setting in which the diamond will be placed. Often, slight colour variations are not visible to the untrained eye, especially when set in jewellery.



Clarity refers to the presence of internal or external imperfections, known as inclusions and blemishes, respectively.

Diamonds with fewer and smaller inclusions and blemishes are rarer and more valuable. Clarity is graded from Flawless (no inclusions or blemishes visible under 10x magnification) to Included (inclusions and/or blemishes visible to the naked eye). Most diamonds have some degree of inclusions, but many are not visible without magnification. When choosing a diamond, consider clarity as it affects the overall appearance and brilliance of the stone. A diamond with higher clarity will have a cleaner look and better sparkle.



The shape of a diamond is one of the most defining aspects of its appearance and character.

Diamonds come in a variety of shapes, each offering a unique style and personality. Round brilliant diamonds are the most popular due to their exceptional sparkle and timeless appeal. Other shapes, such as princess, emerald, oval, radiant and pear, provide alternatives that suit different tastes and preferences. Each shape interacts with light differently, affecting the diamond’s brilliance and the way it looks when set in jewellery. When choosing a diamond shape, consider the wearer’s style and the setting in which the diamond will be placed. The shape you select can enhance the diamond’s visual appeal and complement the overall design of the jewellery piece.


Certification and Grading

When purchasing a diamond, ensuring it comes with a certification from a reputable gemological laboratory is crucial.

Certifications from renowned institutions such as the Gemological Institute of America (GIA) provide an unbiased evaluation of a diamond’s quality based on the 4Cs – Carat, Cut, Colour, and Clarity. These certificates offer a detailed analysis of the diamond’s characteristics, including measurements, proportions, and any inclusions or blemishes. A certified diamond gives you confidence in the authenticity and quality of your purchase, ensuring that the diamond meets the highest standards of excellence.


Lab-Grown Diamonds vs. Natural Diamonds

When choosing a diamond, you have the option of selecting between lab-grown diamonds and natural diamonds.

Lab-grown diamonds: These diamonds are created in a controlled laboratory environment using advanced technological processes that mimic the natural conditions under which diamonds form in the earth. These diamonds are chemically, physically, and optically identical to natural diamonds, ensuring the same level of brilliance and durability.

Natural diamonds: These diamonds are formed over billions of years deep within the Earth’s mantle, carrying a sense of history and rarity. While lab-grown diamonds are generally more affordable and offer an ethical and environmentally friendly alternative, natural diamonds are often prized for their unique origin and natural formation.

Both options have their own set of benefits, allowing you to choose a diamond that aligns with your values, budget, and personal preferences.


Find Your Perfect Diamond

Explore our extensive collection of natural and lab-grown
diamond engagement rings.


Find Your Ring Size

Australia Internal Diameter /
Circumference (mm)​
13.9 / 43.6
F 1/2
14.1 / 44.2
14.3 / 44.8
G 1/2
14.5 / 45.5
14.7 / 46.1
14.9 / 46.7
15.1 / 47.4
I 1/2
15.3 / 48
15.5 / 48.7
J 1/2
15.7 / 49.3
15.9 / 49.9
K 1/2
16.1 / 50.6
16.3 / 51.2
L 1/2
16.5 / 51.8
16.7 / 52.5
M 1/2
16.9 / 53.1
17.1 / 53.8
N 1/2
17.3 / 54.4
17.5 / 55
O 1/2
17.7 / 55.7

How To Measure

  1. Grab a tape measure, length of string or strip of paper.
  2. Wrap it around the finger you'll wear your ring on—if you’re creating a ring stack, consider where on your finger the ring will sit—and mark the place where it joins.
  3. Lay your string or paper strip on a flat surface and use a ruler to measure the length up to the mark. Use the chart above to match the measurement to the closest ring size.
  1. Choose a ring that already fits your finger well.
  2. Measure the interior diameter of the ring in millimeters (mm).
  3. Use the measurement chart above to match the size of your ring to the closest size in mm.

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