The 4Cs of Lab Grown Diamonds Explained
Shopping for a lab grown diamond can feel overwhelming — especially when every jeweller starts throwing around grades, charts and acronyms. This guide cuts through the noise and explains exactly what the 4Cs mean, and which ones actually matter most when choosing your stone.
Cut — The Most Important C
Cut is the single most important of the 4Cs. It has nothing to do with the shape of the diamond (round, oval, pear, etc.) — it refers to how precisely the stone’s facets have been angled and polished to maximise light return. A poorly cut diamond will look dull even if it’s perfectly clear. Look for Excellent or Very Good cut grades on your certificate.
Colour
Diamond colour is graded on a scale from D (completely colourless) to Z (yellow tint). For lab grown diamonds, the sweet spot for value is the G–I range. These grades appear virtually colourless to the naked eye, particularly once set in white gold or platinum. If you’re setting in yellow gold, you can go as low as J–K because the warm metal tone balances any slight colour.
Clarity
Clarity refers to internal inclusions (tiny imperfections) and surface blemishes. The scale runs from Flawless (FL) down to Included (I1–I3). For lab grown diamonds, VS1–VS2 (Very Slightly Included) is the sweet spot — these inclusions are invisible to the naked eye, and you won’t be paying for perfection you can’t see. SI1 can also be eye-clean and offers excellent value.
Carat
Carat is the weight of the stone — 1 carat = 0.2 grams. Larger carats cost more, but going just below a milestone (e.g. 0.90ct instead of 1.00ct) can save significantly with no visible size difference. Because lab grown diamonds are produced in a lab, you can get much larger carat weights for a fraction of the mined diamond price.
What Should You Prioritise?
Start with cut — always. Then set your minimum colour and clarity (G/VS2 is a great starting point), and use the remaining budget on carat. You’ll end up with a stone that looks spectacular without overextending your budget.
Our team at Melia Nae in Macarthur Square, Campbelltown can walk you through certified stones in person, or enquire online about our current lab grown diamond range.