Lab Grown Diamond vs Moissanite Necklace: Which Should You Choose?

Lab Grown Diamond vs Moissanite Necklace: Which Should You Choose?

Both lab grown diamonds and moissanite make excellent necklaces — but they are different gemstones with genuinely different looks. Lab grown diamonds produce white, classic sparkle and carry independent IGI certification. Moissanite produces more vivid rainbow fire, comes at a significantly lower price, and is equally durable for daily wear. Neither is objectively better. The right choice depends on the kind of sparkle you love and the budget that makes sense for you.

Bellari carries both — and that means this guide has no commercial reason to push you toward one. Here is an honest comparison of everything that matters when choosing between a lab grown diamond necklace and a moissanite necklace in Australia.

(explore lab grown diamond necklaces)

What Are They? A Quick Overview

Lab grown diamond is pure carbon, arranged in the same cubic crystal structure as a naturally mined diamond — because it is, chemically and physically, the same material. It is grown in a laboratory over weeks using CVD or HPHT processes, graded by IGI using the 4Cs, and scores Mohs 10 — the maximum hardness any substance can achieve. For more detail, read CVD vs HPHT Lab Grown Diamonds

Moissanite is silicon carbide (SiC) — a completely different compound from diamond, first discovered in a meteor crater in 1893 by French chemist Henri Moissan. Natural moissanite is extraordinarily rare; virtually all moissanite in jewellery today is laboratory grown. It scores Mohs 9.25, has a higher refractive index than diamond (2.65–2.69 vs diamond's 2.417), and a much higher dispersion (fire) rating (0.104 vs diamond's 0.044). For a full comparison, read our Moissanite vs Diamond Australia guide.

What matters for this comparison: how each stone looks in a necklace, how it wears, what certification it carries, and what it costs.

The Full Comparison

Sparkle: The Most Important Difference for a Necklace

This is where the two gemstones genuinely diverge — and where a necklace setting makes the difference particularly visible.

What Diamond Sparkle Looks Like

A lab grown diamond produces what gemologists call brilliance (white light reflected from the stone's facets) and fire (coloured flashes as light disperses into its spectrum). In a diamond, brilliance dominates — the majority of light return is bright white, with subtle coloured fire that adds depth and character without overpowering.

Diamond is singly refractive: light enters the stone and travels as a single ray, bouncing predictably between facets before exiting. This produces the clean, classic sparkle that has defined fine diamond jewellery for centuries — a look most people recognise immediately as "diamond."

What Moissanite Sparkle Looks Like

Moissanite produces significantly more fire than a diamond — its dispersion rating of 0.104 compared to diamond's 0.044 means it breaks white light into coloured spectrum flashes at 2.4 times the intensity. The effect is vivid: bright rainbow flashes of colour that are particularly pronounced in direct sunlight or strong indoor lighting.

Moissanite is also doubly refractive: when a ray of light enters the stone, it splits into two rays that travel through the crystal at slightly different speeds. This creates the characteristic "doubling" of facet reflections visible under magnification, and contributes to moissanite's distinctive, lively fire.

Why the Necklace Setting Specifically Matters

A necklace pendant moves — with your breathing, your walk, the movement of a conversation. That constant motion catches light from constantly changing angles. For moissanite, this movement amplifies its rainbow fire effect, creating a vivid, dynamic display of colour particularly visible in bright environments. For a lab grown diamond, the movement produces a clean dance of white light with subtle coloured sparks.

This is a genuine aesthetic difference, not a quality difference. Some buyers love moissanite's vivid, colourful display — they describe it as "alive" and "spectacular." Others prefer diamond's cooler, more restrained white brilliance. Neither is wrong. They are simply different styles of sparkle.

The stone size matters too. In smaller stones — below 0.5 carat — the difference in sparkle character between moissanite and diamond is subtle and many people don't notice it. In stones above 1 carat, moissanite's rainbow fire becomes distinctly visible and is the primary way an experienced eye would recognise it differs from diamond.

Durability: Both Are Excellent for Daily Wear

For a necklace worn daily — to work, to the gym, in the shower — both gemstones perform exceptionally well.

Lab grown diamond: Mohs 10 — the maximum hardness any natural substance can achieve. Completely scratch-resistant in everyday conditions. Will not cloud, yellow, or change in any way over time.

Moissanite: Mohs 9.25 — second only to diamond on the Mohs scale. For practical daily wear, the difference between Mohs 9.25 and Mohs 10 is insignificant — nothing encountered in normal life (keys, coins, other jewellery) can scratch moissanite. A moissanite necklace will look identical in twenty years with normal care.

For comparison: sapphire is Mohs 9, ruby Mohs 9, emerald Mohs 7.5–8, cubic zirconia Mohs 8–8.5. Both moissanite and lab grown diamond are significantly more durable than these alternatives.

Neither gemstone requires special daily care. Both can be cleaned with warm water, mild dish soap, and a soft brush. Neither needs to be removed for handwashing, moderate exercise, or everyday activity.

Certification: A Meaningful Difference

This is where a practical distinction exists between the two.

Lab grown diamond comes with an independent IGI certificate — a grading report produced by trained gemologists at the International Gemological Institute who have no commercial interest in the outcome. The certificate documents the stone's specific cut grade, colour grade, clarity grade, and carat weight. Each stone's certificate is unique to that stone and verifiable at igi.org using the report number laser-inscribed on the diamond's girdle.

When you buy a Bellari lab grown diamond necklace, you receive that specific certificate and can verify every detail of your stone's grading independently. Read more in our IGI Certification Guide.

Moissanite comes with a manufacturer's certificate of authenticity rather than an independent IGI or GIA grading report. Premium moissanite — including what Bellari uses — is described as D colour equivalent and VVS1 clarity equivalent, but these descriptions are manufacturer claims rather than independently graded assessments. There is no equivalent of the IGI report number that allows you to verify a moissanite stone's grading through a third-party database.

For buyers where independent certification is important — for insurance purposes, for gifting, or for personal assurance — lab grown diamonds have a clearer credential. For buyers for whom sparkle and price are the primary considerations, the manufacturer certificate is sufficient assurance of moissanite quality.

Price: The Significant Moissanite Advantage

Moissanite is dramatically less expensive than lab grown diamond — typically 70–90% less for comparable carat weight. This is not a reflection of moissanite's quality or durability. It is a function of production cost: moissanite is faster and cheaper to produce than lab grown diamonds, which require 4–8 weeks per stone using precision CVD or HPHT processes.

What this means for a necklace buyer in Australia:

A 1-carat lab grown diamond solitaire necklace in 18K gold — IGI certified, Excellent cut, D–F colour, VS1 clarity — sits in a higher price range that reflects the diamond's certified grade and production cost.

A 1-carat moissanite solitaire necklace in 18K gold of comparable appearance is typically available at a fraction of that price.

The budget difference between the two options can be significant — and for many buyers, the question becomes: would you rather have a 1-carat lab grown diamond necklace or a 2-carat moissanite necklace for the same spend? There is no correct answer. It is a genuine trade-off between gemstone type and physical size.

Moissanite's price advantage grows with size. The larger the stone you want, the greater the savings moissanite offers versus diamond. This is why moissanite is particularly popular for statement pieces — tennis necklaces, larger pendants, stacked looks — where diamond would require a significantly higher investment.

The "Can You Tell?" Question

One of the most searched questions about this comparison: can people tell the difference between a moissanite and diamond necklace when you're wearing it?

The honest answer is nuanced.

In most everyday settings: No. Most people — including many jewellers in normal retail settings — cannot identify moissanite versus diamond when seeing a necklace worn in normal lighting. In a dimly lit restaurant, an office environment, or an evening setting, the sparkle difference is not obvious to the untrained eye.

In direct sunlight or bright lighting: The difference is more visible, particularly in stones above 1 carat. Moissanite's vivid rainbow fire is at its most pronounced in bright conditions, and experienced jewellery observers may notice the distinctive coloured flash pattern differs from classic diamond brilliance.

Side by side: The difference is clear. Place a moissanite and a diamond of similar size next to each other in bright light, and the moissanite's more vivid, coloured fire versus the diamond's white brilliance is apparent.

Under magnification: The "doubling" effect of moissanite's double refraction is visible under a loupe — you see two reflected images of each facet edge instead of one. This is one of the technical ways gemologists identify moissanite.

For most buyers, the "can you tell?" question is less important than the sparkle style question: which look do you prefer? Both are beautiful. They simply look different.

Who Should Choose a Lab Grown Diamond Necklace?

A lab grown diamond necklace is the right choice if:

You want the classic diamond look. White, brilliant sparkle without vivid rainbow fire — the look that has defined fine jewellery for generations. If you have always envisioned a diamond and the appearance of a diamond matters to you, a lab grown diamond delivers that authentically.

Independent certification is important to you. The IGI certificate provides objective, verifiable documentation of your specific stone's quality. This matters for insurance, gifting with documentation, or personal confidence that an independent laboratory has assessed the stone.

You are gifting something significant. A lab grown diamond necklace carries the weight of "this is a diamond" — with the IGI certificate to prove it. For milestone gifts — anniversaries, significant birthdays, a meaningful occasion — the certification and the genuine diamond status add substance to the gift.

The white gold setting is your preference. Lab grown diamonds in white gold produce the most refined, classic look — cool, icy, and deeply elegant. The D–F colour of an IGI certified diamond in white gold is hard to surpass for sheer quality of appearance.

Who Should Choose a Moissanite Necklace?

A moissanite necklace is the right choice if:

You love vivid, colourful sparkle. If the rainbow fire and high-energy light play of moissanite is the look that makes you stop and stare, that is the right stone for you. There is nothing inferior about preferring moissanite's sparkle — it is genuinely spectacular, and many buyers choose it precisely because of its distinctive fire rather than despite it.

You want a larger stone for your budget. If you are working within a budget and want the most visually impressive piece possible, moissanite allows you to go significantly larger than lab grown diamond for the same spend. A 2-carat moissanite at the price of a 0.7-carat lab grown diamond is a real comparison — and for a statement necklace, size is visible.

You want a tennis-style necklace. Moissanite's price advantage is most powerful for multi-stone pieces. A moissanite tennis necklace — featuring many stones across the full necklace length — can be achieved at a price point that an equivalent lab grown diamond tennis necklace would multiply dramatically.

Ethical sourcing is a priority but certification is not. Both moissanite and lab grown diamonds are fully ethical and conflict-free. If certification is not essential to you and your primary priorities are sparkle and ethics within a budget, moissanite delivers all of that.

Bellari's Both-Sides Position

Bellari is one of the few fine jewellery brands in Australia that carries both lab grown diamond and moissanite necklaces. That means when Kay from Bellari says "here's when diamond works better and here's when moissanite works better," it is a genuine editorial judgement — not a sales decision.

The right choice between a lab grown diamond necklace and a moissanite necklace is the one that reflects your taste, your budget, and the occasion you are buying for. Both are beautiful. Both are ethical. Both will last a lifetime. They simply deliver a different sparkle.

Bellari's Lab Grown Diamond Solitaire Necklace Collection

IGI certified, made to order in Sydney in solid 18K gold. Four cuts, two metal options.

Round Brilliant

• Round Brilliant Diamond Necklace — 18K Yellow Gold
• Round Brilliant Diamond Necklace — 18K White Gold

Oval

• Oval Diamond Necklace — 18K Yellow Gold
• Oval Diamond Necklace — 18K White Gold

Pear

• Pear Diamond Necklace — 18K Yellow Gold
• Pear Diamond Necklace — 18K White Gold

Emerald Cut

• Emerald Cut Diamond Necklace — 18K Yellow Gold
• Emerald Cut Diamond Necklace — 18K White Gold

Bellari's Moissanite Necklace Collection

Moissanite Tennis Necklace

Bellari's moissanite tennis necklace features individually set moissanite stones across the full necklace length, one of the most dramatic fine jewellery statements available in moissanite. Set in sterling silver with rhodium plating for lasting brightness.

• Moissanite Tennis Necklace

Also available: the Tennis Necklace and Bracelet Set — a coordinated moissanite set for maximum impact.

To explore the full Bellari moissanite range including bracelets:

• Moissanite Tennis Bracelets Collection

Summary

Lab grown diamonds and moissanite are both excellent choices for a necklace in Australia — ethically sourced, laboratory grown, and extremely durable. The key difference is optical: lab grown diamonds produce white, classic brilliance with subtle fire (dispersion 0.044), while moissanite produces vivid rainbow flashes at 2.4 times the fire intensity (dispersion 0.104) due to its higher refractive index and double refraction.

Lab grown diamonds carry independent IGI certification with individually graded 4Cs. Moissanite carries a manufacturer's certificate of authenticity. Lab grown diamonds cost more; moissanite allows a larger stone for the same budget. Both last a lifetime.

Choose by the sparkle you love — and if you are not sure, it genuinely helps to see both in person. If you have further questions, our Sparkle Guide covers how each looks in different settings and lights.

Frequently Asked Questions

What is the difference between a lab grown diamond necklace and a moissanite necklace? Lab grown diamonds are pure carbon (same as mined diamonds) with Mohs 10, refractive index 2.417, and dispersion 0.044 — producing white, classic sparkle. Moissanite is silicon carbide with Mohs 9.25, refractive index 2.65–2.69, and dispersion 0.104 — producing vivid rainbow fire at 2.4 times the intensity of diamond. Both are lab-grown, conflict-free, and extremely durable.

Is moissanite or lab grown diamond better for a necklace? Neither is objectively better. Lab grown diamonds produce classic white sparkle and carry IGI certification. Moissanite produces vivid coloured fire and is 70–90% less expensive. The right choice depends on the sparkle style you prefer and your budget.

Can you tell the difference between a moissanite and diamond necklace? In most everyday settings, no. In bright light or sunlight, moissanite's rainbow fire becomes more pronounced — particularly in stones above 1 carat — and is distinguishable from diamond's white brilliance on close inspection. Side by side, the difference is clear.

Why does moissanite sparkle differently to a diamond? Two reasons: higher dispersion (0.104 vs 0.044 — producing 2.4× more coloured fire) and double refraction (light splits into two rays inside moissanite, creating a distinctive doubling effect). Diamond is singly refractive, producing cleaner, predominantly white sparkle.

Is moissanite durable enough for a necklace worn daily? Yes. Moissanite scores Mohs 9.25 — second only to diamond. It does not scratch, cloud, or lose its sparkle with daily wear. A moissanite necklace will look identical in thirty years with normal care.

How much cheaper is a moissanite necklace than a diamond necklace in Australia? Moissanite is typically 70–90% less than a lab grown diamond of comparable carat weight. A 2-carat moissanite can cost less than a 0.5-carat lab grown diamond of similar visual impact. The price gap grows with stone size.

Is moissanite certified the same way as a diamond? No. Lab grown diamonds carry individual IGI certificates with independent 4Cs grading, verifiable at igi.org. Moissanite carries a manufacturer's certificate of authenticity — a quality statement from the producer, not an independent third-party assessment.

Does moissanite look like a diamond in a necklace? In most lighting conditions, moissanite closely resembles a diamond, particularly in smaller stones. In bright or direct light, moissanite's rainbow fire is more vivid than diamond's white brilliance, and this difference is most visible in larger stones and when the pendant is in motion.

Which is more ethical — moissanite or lab grown diamond? Both are fully ethical. Moissanite is always laboratory grown — there is no moissanite mining. Lab grown diamonds have fully traceable, conflict-free supply chains with no earth disturbance. From an ethical standpoint, both are equivalent choices.

Can moissanite be set in the same solitaire style as a diamond necklace? Yes. Moissanite can be set in any pendant style. Bellari's moissanite necklace collection includes a tennis-style design featuring individually set moissanite stones.

What does 'double refraction' in moissanite mean? Double refraction means light entering moissanite splits into two rays that travel at slightly different speeds. This creates visible "doubling" of facet reflections under magnification and contributes to moissanite's more vivid, colourful fire versus diamond's clean white sparkle.

Does Bellari sell both lab grown diamond and moissanite necklaces? Yes. Bellari carries both IGI certified lab grown diamond solitaire necklaces (four cuts in 18K yellow and white gold) and moissanite necklaces. Both ranges are available — the right choice is whichever suits your style and budget.