Are lab grown diamonds real? Yes — they’re genuine diamonds. Grown from pure carbon in controlled conditions, they share the same crystal structure, hardness, and optical properties as mined stones. Methods such as Chemical Vapour Deposition (CVD) and High Pressure High Temperature (HPHT) replicate nature’s recipe in weeks rather than millennia. To the naked eye, lab and natural diamonds look identical; only specialist instruments can determine origin. The key differences are origin, traceability, pricing, and how the market currently treats resale.

In this guide, we explain what makes a diamond “real”, how CVD and HPHT work, whether you can tell the difference, and how certification (GIA, IGI and laser inscriptions) protects you. You’ll see UK cost comparisons, value and resale realities, the evidence on ethics and sustainability, clear guidance on simulants, and practical buying tips — including the 4Cs — so you can choose with confidence in Hatton Garden or online.

What makes a diamond real?

A diamond is “real” because of what it is, not where it comes from: a crystal of pure carbon with the same physical and optical properties recognised by gemmology. Whether formed underground or grown in a lab, a real diamond will exhibit the brightness, fire and hardness people expect — and it will grade against the same 4Cs.

• Composition: Crystallised carbon with the same chemical makeup.
• Hardness: Measures 10 on the Mohs scale, resisting scratches.
• Optical performance: Bright, crisp sparkle when well cut.
• Independent grading: Assessed by recognised labs using the 4Cs.

On every one of these counts, lab grown diamonds are real. They test as diamonds because they are diamonds; gem labs can still determine origin with specialist instruments (for example, by analysing trace elements like nitrogen). In everyday wear and under a loupe, the experience is the same — authenticity is defined by properties, not provenance.

How lab grown diamonds are made (CVD vs HPHT)

Lab grown diamonds are created by replicating nature’s conditions with precision. Both methods begin with a tiny diamond “seed” and grow new diamond crystal around it, producing authentic crystallised carbon. The two established techniques are Chemical Vapour Deposition (CVD) and High Pressure High Temperature (HPHT).

• HPHT: A diamond grows under intense pressure and heat, closely mimicking the Earth’s mantle. Carbon dissolves and crystallises onto the seed, forming diamond in a matter of weeks. HPHT rough looks distinct pre-cut and, compared with CVD, often needs less post‑growth treatment to refine colour and clarity.

• CVD: A thin diamond seed is placed in a vacuum chamber filled with carbon‑rich gas. Energised gas breaks apart, and carbon atoms deposit in layers onto the seed, building diamond. Some CVD stones can show brownish undertones as grown and may undergo post‑growth treatment to optimise colour and clarity.

Most lab diamonds take roughly 2–4 weeks to form. While CVD, HPHT and natural diamonds look different in their rough state, once cut and polished they appear the same; only specialist laboratory equipment can determine their origin.

Lab vs natural: can you tell the difference?

Short answer: not by eye. Once cut and polished, lab grown and natural diamonds look the same because they share the same crystal structure, hardness and optical properties. They also “test as diamond” on standard diamond testers because they are real diamonds. Separating origin reliably requires specialist laboratory equipment that analyses subtle markers, such as trace elements; for instance, many natural diamonds contain tiny amounts of nitrogen, while lab stones can be grown without it.

• To the eye (and loupe): Indistinguishable in sparkle, colour and clarity at like‑for‑like grades.
• With shop tools: Diamond testers read both as diamond; they are chemically identical.
• With specialist labs: Origin can be determined using advanced instruments that detect features like trace nitrogen and growth signatures.
• In the rough: CVD, HPHT and natural rough look different, but once cut those cues disappear.
• On paper: A grading report will state whether a diamond is natural or lab grown (more on certification next).

Certification and grading (GIA, IGI and laser inscriptions)

Independent certification is your proof of exactly what you’re buying. Lab grown diamonds are graded by the same 4Cs as natural stones, and the most trusted reports come from GIA and IGI. GIA has graded lab diamonds since 2007 with reference to its colour, clarity and cut standards, and reports also note the growth method (CVD or HPHT). Many buyers prefer IGI for lab diamonds because IGI uses the familiar global letter/word grades (e.g., D–Z for colour, VS2, etc.), whereas GIA lab reports have been known to use descriptive terms for colour and clarity.

Both GIA and IGI add a laser inscription on the girdle: a unique report number that matches the certificate. IGI also includes the words “lab grown” alongside the inscription, making origin clear at a glance.

• GIA lab-grown reports: Rigorous grading to GIA standards; origin and growth method disclosed; may use descriptive colour/clarity terms.
• IGI lab-grown reports: Widely adopted for lab stones; uses the standard D–Z and clarity grade scales.
• Laser inscriptions: Unique report number on the girdle; IGI additionally inscribes “lab grown”.
• Origin disclosure: Certificates state “laboratory-grown” and typically indicate CVD or HPHT.

Cost comparison: lab grown vs natural diamonds in the UK

For UK buyers, the biggest practical difference is price. Because lab creation is far more efficient than mining, lab grown diamonds typically cost 60%–85% less than natural diamonds of comparable carat, cut, colour and clarity. Prices vary with the 4Cs and market availability, but the discount is consistent enough that the same budget can usually secure a larger carat or higher quality grade in a lab stone. Here’s a representative snapshot for like‑for‑like round diamonds:

These figures illustrate the current UK market spread: both are real diamonds graded to the same standards, but their origins and production costs differ. The price gap reflects the efficiency of lab growth versus the time, land use and infrastructure required to mine natural diamonds. The result is straightforward: if size or best‑in‑class grades are your priority, lab grown offers more diamond for your money without compromising authenticity.

Value, resale and long-term considerations

If you’re weighing lab vs natural for the long run, focus on use, not speculation. Lab grown diamonds cost far less upfront, but their resale market is still maturing and prices have been falling as production becomes more efficient. Natural diamonds have a more established second‑hand market and tend to retain value better, yet in both cases diamonds are usually poor financial investments. Think of the ring as a lifelong piece of jewellery rather than an asset; the emotional return typically dwarfs any resale math.

• Resale reality: Most diamonds (lab or natural) resell for less than the original purchase price.
• Lab price trajectory: Lab prices have dropped quickly and could continue to evolve; future values are uncertain.
• Natural retention: Naturals generally hold value better due to established markets and perceived rarity, but still not guaranteed.
• Certificates matter: GIA/IGI grading and laser inscriptions support transparency and liquidity when selling or upgrading.
• Appraisal vs resale: Insurance appraisals reflect replacement cost, not what a buyer will pay on the secondary market.
• Practical takeaway: Prioritise the diamond you’ll love wearing every day; both lab and natural are real diamonds, but they behave differently on price over time.

Ethics and sustainability: what the evidence says

If ethics are your decider, the picture is encouraging but nuanced. Lab grown diamonds generally use far less land than mining and avoid the risk of conflict sourcing; they also tend to use less water (around 18 gallons per carat vs roughly 126 gallons for mined) and lower energy overall (circa 250 million joules per carat vs about 538.5 million). They are, however, made with electricity, so the footprint depends on the power mix—some producers now use solar or other renewables, while others do not. On the natural side, the UN’s Kimberley Process makes buying a “blood diamond” near impossible, and ethically run mines can support livelihoods in mining‑dependent communities. In short: lab diamonds can be the lower‑impact choice, but “more ethical” isn’t guaranteed without transparency.

• Ask about energy and origin: Where was the stone grown, and is renewable power used?
• Seek transparency: Full traceability and disclosure of CVD or HPHT growth.
• Rely on paperwork: GIA/IGI reports and laser inscriptions to verify origin.
• Check natural sourcing: Kimberley Process compliance and responsible‑mining assurances.

Lab grown diamonds vs simulants (moissanite and cubic zirconia)

Lab grown diamonds are real diamonds; simulants are not. Moissanite and cubic zirconia (CZ) are engineered to look diamond‑like, but they have different chemistry and optics. That matters in how they sparkle, wear and age. Where a lab diamond delivers crisp white brilliance and lasting hardness, moissanite often shows rainbow‑heavy fire and can look hazy, while CZ gives a softer sparkle, scratches more easily and can yellow over time. If you want diamond performance and authenticity, choose a certified lab grown diamond; if you want a different look at a lower price, know the trade‑offs.

• Lab grown diamond: Crystallised carbon, Mohs 10, bright crisp sparkle; graded by GIA/IGI with laser inscriptions.
• Moissanite: Silicon carbide; fiery, rainbow‑rich sparkle; can show grey/brown/yellow/green tones; doubly refractive so larger stones may look hazy.
• Cubic zirconia (CZ): Very inexpensive; often flawless/colourless at first; lower lustre, scratches more easily, can yellow with wear.
• Quick check: A proper grading report and laser inscription confirm a lab grown diamond and prevent confusion with simulants.

Durability, care and lifespan

Because lab grown diamonds are real diamonds, their durability matches natural stones. They measure 10 on the Mohs scale, resisting scratches and abrasion, and they’ll last just as long as mined diamonds. In daily wear they perform identically; the sparkle you see is the sparkle you keep with routine care. For long‑term brilliance, occasional professional cleaning and a quick check of the setting are sensible. With A Star Diamonds, lifetime polishing and cleaning make upkeep simple throughout the years.

• Hardness and wear: Mohs 10; ideal for everyday jewellery.
• Common‑sense care: Treat like a natural diamond; avoid unnecessary knocks during heavy activity.
• Professional maintenance: Book periodic inspections and cleans; use lifetime polishing/cleaning where provided.
• Paperwork and protection: Keep your GIA/IGI report and consider insurance for peace of mind.

How to choose quality: the 4Cs and beyond

Choosing quality is identical for lab grown and natural diamonds because both are graded on the same 4Cs. Prioritise what you can see: a superb cut for brightness and fire, a pleasing face-up colour, and eye‑clean clarity. Carat is the size lever, but it works best once cut and colour are in place. Always anchor your choice with a GIA or IGI grading report.

• Cut first: For round diamonds, target Excellent cut. For fancy shapes, seek Excellent polish and symmetry and balanced proportions for lively sparkle.
• Colour that suits you: For an icy look, consider D–F; for value without obvious warmth, G–H often works beautifully.
• Clarity you can’t see: VS2–SI1 can be eye‑clean; review magnified images/video rather than chasing higher grades on paper.
• Carat as a final tweak: Adjust size after securing cut, colour and clarity; don’t trade brilliance for a bigger number.
• Fluorescence: Faint to medium can be fine; judge with your eyes and the stone’s video.
• Certification & inscription: Choose GIA or IGI, with a matching laser‑inscribed report number and clear “laboratory‑grown” origin.
• Growth method disclosure: CVD or HPHT is noted on the report; any post‑growth treatment is disclosed—focus on how the diamond looks to you.

Appraisals, insurance and paperwork

Lab grown diamonds can be appraised and insured just like natural stones. An appraisal documents your ring for insurance at its replacement value (not resale value) and should clearly state “laboratory‑grown”, with the grading details taken from your GIA or IGI report. Ask the appraiser to record the laser inscription number and, where disclosed on the certificate, the growth method (CVD or HPHT). In the UK, you can add the ring as a specified item on home insurance or choose dedicated jewellery cover; revalue periodically as lab prices evolve.

• Keep these documents: GIA/IGI report, invoice, high‑resolution photos, laser inscription number, and any maintenance receipts.
• For the appraisal: Ensure a full spec (carat, cut, colour, clarity, metal, maker), “laboratory‑grown” origin, report number and current UK replacement value.
• For insurance: Confirm worldwide cover for loss, theft and accidental damage; check “mysterious disappearance”, away‑from‑home limits, excess and repair policies.
• Good practice: Photograph the ring after any resize or service and store digital copies of all paperwork offsite.

When a lab grown diamond is the right choice

Choose a lab grown diamond when you want real diamond beauty with more flexibility on budget and design. Because they’re priced around 60%–85% below comparable natural stones, you can prioritise a larger carat, higher colour, or superior cut without stretching. They’re also attractive if you value clear origin disclosure and lower land use, while accepting that resale values are less established.

• Maximising size or quality: More carat or top‑tier grades for the same spend.
• Ethics and transparency: Clear “laboratory‑grown” origin, full disclosure, and typically lower land impact; ask about renewable energy.
• Tight timelines: Grown in weeks, ideal for short‑notice proposals or bespoke projects.
• Creative freedom: Easier access to fancy colours and matched stones for modern designs.
• Everyday wear: Same Mohs 10 durability as natural, with GIA/IGI certification and laser inscription.
• Low emphasis on resale: Best for buyers prioritising wear and sentiment over future trade‑in value.

Buying with confidence in Hatton Garden and online

Seeing is believing. In our Hatton Garden studio you can compare natural and lab grown diamonds side‑by‑side, confirm that lab stones are real diamonds, and choose the cut, colour and clarity that sing to you. Our gemmologists, designers and goldsmiths guide you through options, then craft your UK‑made ring in‑house with the personal touches that matter.

• Verify the paperwork: Ask for a GIA or IGI report, match the laser‑inscribed number on the girdle, and note the growth method (CVD or HPHT).
• Judge with your eyes: View under neutral lighting, inspect cut quality and ensure inclusions are eye‑clean at your preferred size.
• Confirm the origin you want: We offer ethically sourced naturals and 100% conflict‑free lab grown diamonds, with full disclosure.
• Assess craftsmanship: In‑house setting in Hatton Garden, secure mountings, complimentary engraving, and lifetime resizing, polishing and cleaning.
• Balance budget and goals: Compare like‑for‑like lab vs natural quotes; discuss resale expectations openly.
• Shop your way: Visit by appointment, or book an online consultation; we can share high‑resolution imagery and certificates before you decide.

Frequently asked questions

Here are straight answers to the questions we’re asked most about lab grown diamonds. Use them as a quick reference, then compare stones side‑by‑side to decide what feels right for you.

• Are lab grown diamonds real? Yes. They’re crystallised carbon with the same properties as mined diamonds.
• Do they test as diamond? Yes. Standard testers read them as diamond; only specialist labs can confirm origin.
• Can you tell lab vs natural by eye? No. At like‑for‑like grades they look identical once cut and polished.
• Who certifies them? GIA and IGI grade lab diamonds on the 4Cs; reports and laser inscriptions verify origin.
• How much cheaper are they? Commonly 60%–85% less than comparable natural stones in the UK.
• Do they last as long? Yes. Mohs hardness 10, the same durability and lifespan as natural diamonds.
• Are they more ethical/sustainable? Often lower land and water use; impact depends on energy source—ask for transparency.
• Are they the same as moissanite or CZ? No. Those are simulants with different chemistry and optics.
• What about resale value? Less established and typically lower than naturals; diamonds in general aren’t investments.
• Can I insure one? Yes. Appraise and insure just like a natural; include the GIA/IGI number and “laboratory‑grown” on paperwork.

Final thoughts

Here’s the simple truth: lab grown diamonds are real diamonds. They share the same chemistry, hardness and sparkle as natural stones; the key differences are origin, price and current resale. With GIA or IGI certification and a laser inscription, you can buy confidently and often secure more carat or higher grades for the same budget.

Whether you prefer nature’s rarity or modern precision, choose the piece you’ll enjoy every day and ask for clear sourcing and energy details. To compare lab and natural side‑by‑side and craft a ring in Hatton Garden, speak with our gemmologists or begin online at A Star Diamonds.