Lab diamonds don't hold value the way mined diamonds have traditionally been marketed to. That's the honest answer, and it's worth understanding before you buy, not as a reason to avoid a lab diamond, but so you're buying it for the right reasons.
The reality
Lab-grown diamond prices have fallen substantially as production technology has become more efficient and scaled up worldwide. A lab diamond bought new today costs meaningfully less than an equivalent stone did a few years ago, which is genuinely good news if you're buying now, but it means the resale value of a stone bought earlier reflects today's lower new-purchase price, not what was originally paid for it. This doesn't make a lab diamond a bad choice for an engagement ring. It means it should be understood as a purchase, not an investment. The same is broadly true of mined diamond jewellery too once retail margin is accounted for, the difference is that the price decline in lab-grown has been sharper and faster.
Why prices have fallen
Lab diamonds are produced using two methods, HPHT (High Pressure High Temperature) and CVD (Chemical Vapour Deposition), and both have become significantly more efficient as the technology has matured. More manufacturers, more production capacity, and faster cycle times have all pushed supply up quickly, and when supply grows faster than demand, prices fall. There's no clear sign of that trend reversing in the near term.
What the resale market actually looks like
Second-hand diamond jewellery, mined or lab-grown, rarely gets close to its original retail price on resale. Retail pricing includes margin for design, manufacturing, and overhead, none of which comes back on the secondary market. A lab diamond without an IGI or GIA certificate is genuinely difficult to sell, since the certificate is the only independent way a buyer can verify what they're getting. The metal setting itself adds little resale value either, second-hand buyers typically pay close to melt value for the metal, not for the craftsmanship. A lab diamond ring is a piece of jewellery with sentimental and aesthetic value, not a financial asset, and evaluating it primarily as an investment misses what it actually is.
How to think about it
If you're choosing a lab diamond because you want a larger, better-quality stone at your budget than an equivalent mined diamond would give you, that's a sound reason, and lab diamonds deliver genuinely superior value per carat for buyers who want a beautiful ring rather than a financial instrument. If you're choosing one because you expect it to hold or gain value over time, the current market doesn't support that expectation, prices are moving the other way. If value preservation is a real priority for you, a certified mined diamond, or moissanite, bought specifically for its beauty at a fraction of diamond pricing, are both more honest choices to make with that goal in mind.
How mined diamond compares
Natural mined diamonds have historically held value better than lab-grown, largely because supply is constrained by geology and mining economics rather than manufacturing scale. That said, the idea that mined diamonds are a strong investment is also overstated, retail-to-resale losses of 30 to 50 percent are common there too. The real difference is that mined diamond prices have stayed relatively stable over long periods, while lab diamond prices have declined faster. If value retention genuinely matters to you, a certified mined diamond is the more defensible choice of the two, though our own view is that most buyers are better served choosing the stone they actually love and can afford, and treating the ring as what it is.
Frequently asked questions
Do lab-grown diamonds hold their value?
Generally not. Prices have declined significantly as production has scaled, so a lab diamond bought today will likely have a lower resale value than its original purchase price, as with most jewellery.
Why have lab diamond prices fallen?
Production technology for both HPHT and CVD has become significantly more efficient, and supply has grown faster than demand. Both push prices down.
Is a lab diamond a good investment?
No, it should be treated as a purchase, not an investment. The same is broadly true of mined diamond jewellery, though the decline has been sharper for lab-grown.
Do mined diamonds hold value better than lab diamonds?
Historically, yes, since mined supply is constrained by geology. They still lose significant value on resale relative to retail price, just less dramatically than lab-grown has recently.
Read our full lab-grown vs mined diamond comparison, browse the lab diamond engagement ring collection, or start a free design consultation to talk through which stone makes sense for what you actually want from it.