You have made the decision. Maybe it came after hours of scrolling, or maybe it settled the way important things do: gradually, and then all at once. You want a diamond. Not just any diamond. One that feels chosen with care, worn with pride, and backed by a story you actually believe in.
Then you opened a jewellery website and ran into a wall of terms you had never heard of. CVD. HPHT. VS1. IGI certified. Eye clean. The world of lab grown diamonds has its own language, and at first it can feel designed to confuse you rather than guide you.
But honestly, it is not. Every term exists for a reason. And once you understand what each one means, the whole process of choosing your diamond becomes less like navigating a test and more like making an informed, personal decision. You stop second-guessing and start deciding.
Whether you are looking at solitaire rings, delicate neckpieces, or everyday earrings, this glossary is for you. It covers the terminology you will actually encounter when exploring lab grown diamonds, and it explains each one simply and clearly.
First, One Distinction Worth Making Early
Lab created diamonds are not diamond simulants. This is one of the most important things to understand before anything else.
Materials like cubic zirconia (CZ) or moissanite are often confused with lab grown diamonds, but they are chemically and physically different. They look similar, but they are not diamonds.
A lab grown diamond, on the other hand, is composed of pure carbon, carries the same crystal structure as a mined diamond, and measures 10 on the Mohs hardness scale. It is, by every scientific and gemological definition, a real diamond. You may also see it referred to as a lab created diamond or an LGD diamond. These terms all describe the same thing.
The Glossary: Terms You Will Actually Encounter
Before getting into the details, it helps to understand the main types of lab grown diamonds you will encounter. While they may look the same, they are created using different growth processes, a distinction that shapes the terminology ahead.
Growth Technologies
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CVD (Chemical Vapour Deposition): In the CVD process, a thin diamond seed is placed inside a vacuum chamber. A hydrocarbon gas, usually methane, is introduced and energised by heat. Carbon atoms break away from the gas and deposit onto the seed, layer by layer, over several weeks. The result is a fully formed diamond crystal. CVD diamonds are known for exceptional purity and are widely used in fine jewellery today.
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HPHT (High Pressure High Temperature): HPHT replicates the conditions deep within the Earth where natural diamonds form. A diamond seed is subjected to extreme pressure and temperatures above 1,400 degrees Celsius. The carbon surrounding it slowly crystallises into a diamond. HPHT is one of the earliest methods of growing diamonds in a laboratory and remains widely used.
Both CVD and HPHT produce diamonds of exceptional quality. The method used to grow a diamond does not determine which one is better. What truly defines its beauty and value is how it performs across the 4Cs: cut, colour, clarity, and carat.
Some lab grown diamonds may undergo post-growth processes to refine their colour or clarity. These enhancements are standard within the industry and are always disclosed in certification. What matters is not whether a diamond has been treated, but that its final quality is transparently graded and accurately represented.
The 4Cs: Your Quality Framework
The 4Cs are the universal standard for evaluating any diamond. Understanding each one changes how you read a certificate and how you shop.
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Cut: Cut refers to how well a diamond has been faceted and proportioned, not the shape it takes (round, oval, pear, emerald, and so on). A well-cut diamond directs light back to your eye with brilliance and sparkle. Grades range from Excellent to Poor. Cut is widely considered the most important of the 4Cs, because even a diamond with superior colour and clarity will look dull if it is poorly cut. At Keemti, our rings and earrings are designed with cut quality as a foundation, because a diamond that performs beautifully in everyday light is one you will want to wear every day.
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Colour: Diamond colour is graded on a scale from D to Z. D, E, and F are colourless, the highest tier. G through J are nearly colourless and still appear white to the naked eye in most settings. From K onwards, a faint yellow or brown tint becomes more visible. For most lab grown diamonds in jewellery, the G to H range offers an excellent balance of quality and value without sacrificing the bright, white appearance.
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Clarity: Clarity measures the presence and nature of inclusions (internal characteristics) and blemishes (surface features) within a diamond. The scale runs from FL (Flawless) to I3 (Included). For everyday jewellery, VS1 to SI1 is a widely recommended range. Diamonds in this range are typically eye clean, meaning no inclusions are visible to the naked eye at a normal viewing distance. They look brilliant without carrying the price of a flawless grade.
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Carat: Carat is a measure of a diamond's weight, not its size. One carat equals 0.2 grams. Two diamonds of the same carat weight can appear different in size depending on their cut and shape. Carat weight significantly affects price, but it works alongside cut, colour, and clarity to determine how a diamond looks in person. A smaller, well-cut diamond can outshine a larger, poorly cut one.
Certification and Grading
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Gemological Certification: A gemological certificate is a report issued by an independent laboratory that documents the 4Cs of a specific diamond. It is your assurance that the quality you are being sold has been assessed by a third party, not just the seller. Always ask for a certificate when purchasing a diamond.
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IGI (International Gemological Institute): IGI is the most widely recognised certifying body for lab grown diamonds globally. Their reports are detailed, standardised, and respected across the industry. An IGI certificate is a strong indicator that the diamond has been rigorously assessed.
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SGL (Solitaire Gemological Laboratories): SGL is a recognised certifying laboratory that holds particular prominence in the Indian market. Many buyers and jewellers in India trust SGL certification for both mined and lab grown diamonds.
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Laser Inscription: Most certified lab grown diamonds carry a laser inscription on the girdle, which is the widest edge of the diamond. This inscription is microscopic and typically includes the words "Lab Grown" along with the unique report number that corresponds to the diamond's certificate. It is a permanent, non-damaging mark that ensures full transparency about the diamond's origin.
Clarity Terminology
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Eye Clean: A diamond is described as eye clean when no inclusions are visible to the naked eye when viewed from about 25 to 30 centimetres away. Eye clean does not mean flawless. It means that any internal characteristics require magnification to be seen. For most buyers choosing jewellery to wear, an eye clean diamond is the practical and beautiful choice.
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Inclusions: Inclusions are internal characteristics that form during a diamond's growth, whether in a laboratory or in the Earth. They can appear as tiny crystals, feather-like formations, clouds, or needles. Their type, size, location, and number determine a diamond's clarity grade. Inclusions are not defects in a damaging sense. They are part of a diamond's individual identity and history of formation.
Ethics, Value, and Things Worth Asking About
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Conflict-Free: Lab grown diamonds have no association with conflict mining. Their origin is fully traceable, from seed to setting. This is not just a talking point. For many buyers, it is the deciding factor.
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Sustainability: Mining for natural diamonds displaces land, consumes enormous water resources, and leaves lasting environmental impact. Lab grown diamonds avoid this entirely. The energy used in production is decreasing as technology improves, and many manufacturers, including those Keemti works with, are moving toward cleaner energy sources.
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Availability: Unlike mined diamonds, which are finite and dependent on geographic conditions, lab grown diamonds can be produced consistently. This is what makes Keemti's accessible pricing possible: not a compromise on quality, but a supply chain that does not depend on scarcity. It also means greater choice. More shapes, more sizes, more possibilities, all available without the wait or the markup that comes with rare mining conditions.
A Note on Lab Diamond Terminology
You will come across several terms that all refer to the same thing: lab grown diamond, lab created diamond, man made diamond, synthetic diamond, LGD. These are not different categories. They describe the same product. The variation in language comes from different parts of the industry using different conventions. When in doubt, ask for the gemological certificate. It will confirm everything clearly.
A Choice You Understand, A Piece You Keep
Knowledge changes everything about how you shop. Once you understand what a VS1 clarity grade actually means, or why the cut matters more than people realise, or what a laser inscription is there to tell you, the experience shifts. You are no longer hoping a piece is right. You know it is.
At Keemti, our rings, neckwear, and earrings are built around this kind of transparency: lab grown diamonds that are certified, ethically created, and priced so that celebrating yourself, now and again and again after that, does not have to wait for a perfect moment.
The diamond you choose is a marker of something real in your life. It deserves to be chosen with full understanding.
