
Your Guide to Choosing the Perfect Diamond
Choosing a diamond can feel confusing, especially if you’re new to jewellery shopping. At Astella, we want to make it easy and enjoyable. Whether you’re looking for engagement ring, or a beautiful piece of diamond jewellery, this guide explains everything you need to know, in simple terms, to find a diamond that’s perfect for you.
The 4 Cs of Diamonds - What You Need to Know

Cut: How Your Diamond Sparkles
The cut is how well the diamond has been shaped and faceted by the jeweller. It controls how light bounces inside the diamond, making it sparkle and shine.
- A well-cut diamond will sparkle more, regardless of its carat weight.
- Cuts are graded from Excellent (the best sparkle) to Poor (less sparkle).
- Popular cuts include the classic round brilliant (the sparkliest), as well as princess, emerald, oval, marquise, and others.

Colour: How Clear or White Your Diamond Looks
Diamonds naturally come with a tiny hint of colour, usually yellow or brown tones. Colour is graded from D (colourless) to Z (noticeable yellow or brown).
- The less colour, the rarer and more valuable the diamond.
- D-F are truly colourless; G-J appear nearly colourless to the naked eye and often offer better value.
- Some people prefer a warmer colour tone, especially when paired with yellow or rose gold.

Clarity: How Clear Your Diamond Is
No diamond is perfect, natural tiny flaws (called inclusions) or surface marks (blemishes) exist in most diamonds.
- Clarity describes how many and how visible these imperfections are.
- The scale goes from Flawless (no imperfections visible even under magnification) to Included (inclusions easily visible).
- Many imperfections are microscopic and don’t affect how beautiful the diamond looks to the naked eye.

Carat: The Weight and Perceived Size
Carat is how we measure the weight of a diamond, not its size or how big it looks.
- 1 carat equals 0.2 grams, about the weight of a paperclip.
- Bigger carat means a heavier diamond, but the way a diamond is cut also affects how large it appears.
- So, two diamonds with the same carat might look different in size because of their shapes and how well they’re cut.
When choosing a diamond, balance carat with quality, a well-cut smaller diamond can sparkle more than a big poorly-cut one.Bigger diamonds cost more but don’t always look bigger depending on the cut. The perfect diamond balances carat weight with cut, colour, and clarity for maximum sparkle and value.
Choosing the Right Diamond Shape for You
Diamonds come in many shapes, each with its own look and personality. Here are a few popular ones:
Square with sharp corners and lots of fire.
The most classic, known for its sparkle.
Rectangle with long facets for a sophisticated look.
Elongated round shape, flattering on many fingers.
A pointed, boat-like shape that makes fingers look longer.
A graceful mix of round and marquise.
Square and vintage-inspired with bold facets.


What About Ethical and Lab-Grown Diamonds?
We care about where your diamond comes from.
All our natural diamonds follow the Kimberley Process Certification, which ensures they are conflict-free and responsibly sourced.
We also offer stunning lab-grown diamonds, real diamonds created in a lab instead of mined from the earth. They have the same sparkle and physical properties but with a lower environmental impact and often at a better price.

How to Choose Your Diamond with Confidence
- Ask for an independent grading report from trusted labs like GIA or IGI, this tells you exactly what you’re buying.
- Think about how you’ll wear your ring or jewellery daily to choose the right setting and metal.
- Remember that the cut affects sparkle the most, a smaller, well-cut diamond can look more brilliant than a larger one with a poor cut.
- Book a personalised consultation with our experts at Astella Jewellery, we guide you through the process and help design your dream ring.