Home › Guides › The 4Cs of Lab Grown Diamonds, Made Simple Lab grown diamond guide The 4Cs of Lab Grown Diamonds, Made Simple Cut, colour, clarity and carat decide how a diamond looks and what it costs. Lab grown diamonds are graded on the same 4Cs as mined diamonds. Here is what each one means and what we suggest. By Vinay Mutha, in the diamond trade in Zaveri Bazaar, Mumbai since 1999 · Updated 6 Nov 2026 On this page1. Cut – the most important C for sparkle2. Colour – how white the diamond is3. Clarity – tiny marks inside the stone4. Carat – weight, not sizeOur quick picksNext steps 1. Cut – the most important C for sparkle Cut is how well the diamond's facets are shaped and angled. A well cut diamond returns light to your eye; a poorly cut one looks dark or glassy even if its colour and clarity are high. For round diamonds choose Ideal or Excellent cut. For fancy shapes (oval, pear, emerald and others) look for Excellent or Very Good polish and symmetry, and look at the photo or video for an even, lively sparkle. 2. Colour – how white the diamond is Colour is graded from D (completely colourless) through E, F, G, H and down the alphabet. D–F are "colourless", G–J are "near colourless". Most lab grown diamonds sold today are in the D–H range. White gold or platinum-look settings: choose D–F for an icy white look. Yellow or rose gold: G–H looks white too, because the warm gold colour reflects into the stone. A good place to save money. 3. Clarity – tiny marks inside the stone Clarity grades the small inclusions and surface marks seen under 10× magnification: GradeWhat it meansSeen by eye? FL / IFFlawless / internally flawlessNo VVS1 / VVS2Very, very slightly includedNo VS1 / VS2Very slightly includedNo (in almost all stones) SI1 / SI2Slightly includedSometimes, in bigger stones For lab grown diamonds, VVS and VS clarities are easy to find. VS1 is the "sweet spot": clean to the eye, and you are not paying extra for marks nobody can see. 4. Carat – weight, not size One carat is 0.2 grams. The carat weight is not the same as how big the diamond looks from the top – that also depends on the shape and cut. An oval or pear of the same weight looks larger than a round because more of its weight is spread across the top. Price rises steeply at popular weights such as 1.00 ct and 2.00 ct; a 0.90 ct or 1.90 ct can look almost the same for less. Our quick picks PieceSuggested grades Solitaire engagement ring (white gold)Excellent cut, D–F, VVS2–VS1 Solitaire ring (yellow / rose gold)Excellent cut, E–H, VS1–VS2 Stud earrings and pendantsVery Good cut or better, F–H, VS Next steps Check the grades on the certificate (how to read an IGI report), then choose your shape: round, oval, pear, emerald. Or go straight to lab grown diamond rings. Frequently asked questions Which of the 4Cs matters most?Cut, because it decides how much the diamond sparkles. After that, choose colour to suit your gold and keep clarity clean to the eye (VS1 or better).What colour and clarity should I buy for an engagement ring?A safe choice is Excellent cut, D–F colour and VVS2–VS1 clarity for white gold. In yellow or rose gold, G–H colour looks white and costs less.Does a 1 carat oval look bigger than a 1 carat round?Yes, usually. Elongated shapes like oval and pear spread more of their weight across the top, so they look larger face up than a round of the same carat weight. More guidesLab Grown vs Natural Diamonds: What Is Really Different?How Are Lab Grown Diamonds Made? CVD and HPHTIGI Certificate Guide: How to Read and Verify a Lab Grown Diamond Report14K vs 18K Gold: Which Is Better for Your Diamond Jewellery?Diamond Shapes Guide: Find the Shape You LoveHow to Clean and Care for Your Diamond Jewellery