A trade primer on the 4Cs, shapes, grading and certification.
From carbon seed to certified diamond — the CVD and HPHT growth process, explained. Every Nuriel stone is grown using one of these two methods and certified by IGI before it enters our vault.
Two methods — Chemical Vapour Deposition (CVD) and High Pressure High Temperature (HPHT) — over six to eight weeks in a controlled chamber. A diamond seed, a carbon source, energy. The result is the same crystal lattice, the same hardness, the same brilliance. The only thing missing is the mine.
Lab-grown diamonds are graded on the same scales as mined — by the same labs. Nuriel uses IGI, the specialist for lab-grown reports. Every stone is laser-inscribed with its report number on the girdle, so it's verifiable for the life of the stone.
To the naked eye, G–H colour is indistinguishable from D–E — but typically 15–20% better value per carat. VS1–VS2 is reliably eye-clean across all shapes and sizes. For most engagement and bespoke work, this bracket gives the client the best mix of size, brilliance and budget. We stock this range in every shape.
Our core stock focuses on the grades that move — D–H colour, VVS1–VS2 clarity, Excellent cut, 0.30ct to 5.00ct. We carry Round, Oval, Cushion, Pear, Marquise, Heart and Radiant. We hold VVS1 and VS2 in the highest volume. All stones IGI certified before they enter our vault.
Round brilliant remains the benchmark for light performance. Oval and pear create the illusion of greater size per carat. Cushion suits vintage and halo settings. Marquise elongates the finger beautifully. Heart requires skilled setting. Radiant suits channel and bezel work. Ask Lira to search by shape, carat and budget.
Every Nuriel stone arrives with an IGI report covering the 4Cs, fluorescence, laser inscription number, proportions and plotting diagram. The report number is laser-inscribed on the girdle — verifiable under 10× magnification. IGI is accepted by all major insurers and valuers in New Zealand and Australia.
Inside the Trade Desk, Lira — our lab-grown specialist — is online 24/7 to walk a client through any of this in real time. Voice or text.