Moissanite vs lab diamond vs mined: the real cost breakdown

Updated 6 August 2026·Written by the Aqua Gold workshop, Ontario.

Moissanite costs the least of the three to produce, a lab-grown diamond costs more than moissanite but less than a mined one, and a mined diamond costs the most. That order has nothing to do with which stone looks better or wears better. A lab-grown diamond is chemically identical to a mined one. What actually separates the three is how each comes to exist: two of them are made to order in a matter of weeks, and one takes over a billion years and then has to be found.

Why does a mined diamond cost more than a lab-grown one or moissanite?

A mined diamond forms roughly 150 to 200 kilometres down, where temperatures reach 900 to 1,300°C and pressure runs into the tens of thousands of atmospheres. That conversion of carbon into diamond takes, by geological estimates, somewhere between one and three billion years, and the stone then has to be carried up by a kimberlite eruption, found, extracted, cut and moved through a supply chain controlled by a small number of major producers. None of that can be sped up on demand.

A lab-grown diamond is the same carbon crystal, grown inside a reactor instead of the earth’s mantle, by high-pressure high-temperature (HPHT) or chemical vapour deposition (CVD). Either way, a cuttable stone typically takes days to a few weeks. Because supply can expand to meet demand, lab-grown diamonds sit well below mined ones on relative cost, though still above moissanite.

Moissanite is a different material again: silicon carbide, grown as a bulk crystal by a process that is faster and more scalable than either diamond method. That is what actually sets moissanite’s relative cost apart, not a difference in how well it performs in a ring or a pair of earrings.

Are lab-grown and mined diamonds actually the same stone?

Yes, materially. Both are pure carbon crystallised into the same cubic lattice. Both score 10 on the Mohs scale, both have a refractive index of 2.42 and a dispersion of 0.044. Nothing about how either one catches light is different.

Telling them apart takes specialised equipment, not a jeweller’s eye. Instruments such as DiamondView use short-wave ultraviolet light to read growth patterns and fluorescence that differ between a stone grown slowly under mantle pressure and one grown in a reactor. There is no reliable handheld test for this, and the dependable answer comes from the laboratory report itself.

That report is also where the two currently diverge. Since late 2025, GIA has stopped issuing detailed colour and clarity grades for lab-grown diamonds, replacing them with two broad categories, Premium and Standard, while mined diamonds still receive the full D-to-Z colour and FL-to-I3 clarity scales. IGI has made no such change and still grades lab-grown stones on the same detailed scale used for mined ones. So whether the two are “graded the same way” now depends on which laboratory issued the report.

Is moissanite graded the same way diamonds are?

No, not in the way a mined or lab-grown diamond is. GIA does not issue a full 4Cs diamond-style report for moissanite; at most it will confirm what the stone is, without a cut, colour or clarity grade on the diamond scale. Some moissanite is sold with a GRA (Gemological Research Association) certificate stating a colour grade, cut and carat-weight equivalent, but GRA does not carry the same institutional weight as GIA or IGI.

A lot of the industry, sellers included, borrows diamond clarity language such as “VVS1” as shorthand for a high visual-clarity tier in a moissanite listing, including on our own tennis bracelet. That is a convention, not a certified independent grade sitting on the same footing as an actual diamond report, and it is worth knowing before you weigh a “VVS1 moissanite” listing against a VVS1-graded diamond. They are not the same kind of claim, even when they use the same letters.

Which of the three holds resale value best?

Mined diamonds generally retain more of their original value on resale than lab-grown diamonds. Natural stones stay finite; lab-grown supply can keep expanding to meet demand, and that has pushed lab-grown resale values down substantially over the past several years, even as the rate of decline has begun to slow.

Moissanite sits furthest from anything resembling an investment case. Without independent 4Cs-style grading, geological scarcity or an established secondary market, most jewellers will not buy a moissanite stone back at all; resale, where it happens, depends on finding an individual buyer.

If resale matters to your decision, that ordering — mined ahead of lab-grown ahead of moissanite — reflects the economics behind each stone, not a judgement on how any of them looks or wears day to day. We covered a related identification question in an earlier piece, on whether moissanite passes a diamond tester, which is worth a read if your concern is less about resale value and more about how confidently a stone can be identified later on.

So which one should you actually buy?

It depends on what you are actually optimising for, and being honest about that upfront avoids disappointment later.

If an established resale and trade market matters to you, a mined diamond is the only one of the three with a real one. If you want a chemically identical stone at a lower relative cost and resale is not the point, lab-grown is the honest middle option, with the caveat that its resale value has fallen a long way. If you want the most durability and visible fire for the lowest relative outlay, and you treat resale as effectively zero, moissanite is the straightforward choice.

We work in moissanite because that last trade-off suits how most of our customers actually buy: strong daily-wear durability and visible fire in a piece like the floating solitaire necklace or the eternity band, without needing the stone to double as a financial asset.

See the fire for yourself

Every piece below is moissanite set on 925 sterling silver, and every listing describes it as moissanite, not diamond.

• Moissanite eternity bandstones set the whole way round, three stone sizes
• Floating solitaire necklacea single stone in a near-invisible setting
• Moissanite stud earringsseveral sizes, in two finishes
• Moissanite tennis braceleta continuous line of prong-set stones
• Marquise-cut moissanite ringan elongated cut that reads larger on the finger
• Moissanite cross pendantgold or rhodium tone
• Sterling silver moissanite crosstwo sizes, on a 16–18 inch or 20 inch chain
• Moissanite Miami cuban link bracelettwo widths

Browse the full range by category — rings, earrings, bracelets and necklaces — or start with our best sellers.

Common questions

More questions

We cover shipping, returns, sizing and payment on our FAQ page. Anything not answered there, get in touch and someone from the workshop will reply.

References

Diamond formation depth, temperature and age figures reflect published geological research on kimberlite-hosted diamonds, not jewellery marketing copy. Mohs hardness, refractive index and dispersion figures for diamond and moissanite are established gemological constants. GIA’s move to a Premium/Standard grading system for lab-grown diamonds took effect in late 2025; earlier GIA lab-grown reports carrying full 4Cs grades remain valid records of what was graded at the time. IGI’s grading practice for lab-grown diamonds was current as of publication and may change.