Lab Grown Diamonds: Understanding the Essentials

“Laboratory-grown diamond”, “laboratory-created diamond” and “synthetic diamond” describe the same origin category. CIBJO recognises these terms as synonymous in its terminology guidance. In this context, “synthetic” describes how the diamond was produced. CIBJO laboratory-grown diamond guidelines.

Other descriptions answer different questions. A loose diamond is an unset stone. Its description should still identify whether it is natural or laboratory-grown.

A certified lab grown diamond usually means a stone accompanied by a laboratory report. The useful information is in the document itself: who issued it, which diamond it describes and what the laboratory assessed. A grading report and a financial appraisal serve different purposes. IGI laboratory-grown diamond reports.

Keeping these descriptions separate makes product listings easier to understand. Origin, setting status and grading documentation each tell you something different.

Two principal methods are used to grow laboratory-grown diamonds.

High Pressure High Temperature, or HPHT, uses high pressure and heat to grow diamond from a carbon source around a seed.

Chemical Vapour Deposition, or CVD, uses a carbon-containing gas inside a controlled chamber. The gas is activated, allowing carbon to build up on a diamond seed in successive layers.

These are different production processes. HPHT can also be used as a treatment after growth, so the growth method and any subsequent treatment are separate details to understand. GIA’s explanation of diamond growth methods.

Natural diamonds form through geological processes; laboratory-grown diamonds are produced using technology. Both belong to the diamond category.

Moissanite and cubic zirconia are different materials that can resemble diamond. They are described as diamond simulants when used for that purpose. A comparison between diamond origins therefore asks a different question from a comparison between gemstones. GIA’s guide to diamond simulants and laboratory-grown diamonds.

Our dedicated comparison guides explore these choices in more detail. You can find them in the guide directory below.

The familiar 4Cs—cut, colour, clarity and carat weight—provide a starting point for understanding diamond quality.

Cut concerns the way a diamond’s facets and proportions interact with light. It affects brightness, coloured flashes and the changing pattern of sparkle as the diamond moves. Shape describes its outline, such as round, oval or pear. Two stones with the same outline can still perform differently in light. GIA’s guide to diamond cut.

Colour and clarity describe other characteristics of the stone. Colour assessment follows a defined viewing method, while clarity considers internal and surface features under magnification. These assessments help explain differences between individual diamonds. IGI’s grading process for laboratory-grown diamonds.

Carat measures weight. It does not give a complete description of visible size. When comparing stones, consider their measurements and proportions alongside the carat figure. GIA’s explanation of carat weight.

For a fuller introduction, explore our Diamond 4Cs guide and diamond shapes guide.

A laboratory report documents the characteristics covered by that particular service. Start with the laboratory name, report type and identifying number, then read the results and comments. Check the report number through the issuing laboratory’s own verification service. IGI’s report information and verification guidance.

Report formats differ. GIA’s current quality assessment for eligible colourless to near-colourless laboratory-grown diamonds uses Premium and Standard categories. GIA also offers separate services for laboratory-grown coloured diamonds. The document’s actual format matters when interpreting its results. GIA laboratory-grown diamond services.

The dedicated IGI and GIA guides below explain how to approach these documents in more detail.

Choose your next guide according to what you need to understand.

If you are choosing a centre stone for a ring or pendant, the quality, report and loose diamond guides provide a useful reading path.

If you are purchasing for a jewellery business, begin with the wholesale overview, then move to supplier selection and the sourcing workflow. The bulk guide addresses purchases involving multiple loose stones.

Before using a price example, establish what it describes. An unset diamond, a finished ring and a parcel of stones are different purchases.

Use the pricing guide to understand comparisons, then move to the relevant buying guide for your intended purchase. When requesting a quotation, specify the diamond requirements and ask what the quoted amount includes. This gives the conversation a clearer starting point than a carat figure alone.

Responsible sourcing involves working conditions, environmental practices, product disclosure and the way a supply chain is managed. These areas are addressed in the Responsible Jewellery Council’s standard for laboratory-grown materials. RJC laboratory-grown materials standard.

When a seller makes an environmental or sourcing claim, ask what it covers and what evidence supports it. This provides information beyond the stone’s origin label or grading results.

If you would like help applying this information to a purchase, contact Uniglo Diamonds. Share the intended jewellery piece or business requirement, preferred shape, approximate size and any report preferences so the discussion can focus on the details that matter to you.