Prices, Costs, and Resale

The price of a laboratory-grown diamond is not a physical property of the material. It is formed within a market chain that includes the cost of growth, polished yield, processing, grading, financing, inventory, distribution, the retailer, brand, and current supply and demand.

Because production is developing exceptionally quickly, figures in this chapter must have a date, market, currency, product specification, and source. An undated claim about the “price of a laboratory-grown diamond” becomes inaccurate very quickly.

Seven Economic Levels That Must Not Be Confused

Production cost is the cost of creating rough. Wholesale price is the transaction price between professional participants. Retailer acquisition cost includes the retailer’s actual purchasing terms. Retail price is the offer to the final customer. Appraisal value, replacement value, and resale value serve different purposes and must not be treated as synonyms.

If a stone was purchased for 2,000 euros, that does not mean its production cost was 2,000 euros, that the retailer can buy it back for 2,000 euros, or that an appraisal of 4,000 euros represents its current cash market price.

What Makes Up Production Cost

For CVD, cost includes the seed or substrate, reactor, microwave system, gases, energy, cooling, maintenance, labor, depreciation, failed growth runs, and losses in converting rough into a polished stone. HPHT has a different structure: high-pressure press, cell, graphite carbon source, metal solvent-catalyst, energy, consumables, labor, and yield.

After growth, costs may include HPHT annealing, irradiation, cutting, polishing, repolishing, grading, laser inscription, logistics, and insurance.

The statement “production costs X per carat” is therefore meaningless without defining what X includes and whether it refers to rough or polished output.

Rough Is Not Polished

As with a natural diamond, some weight is lost during cutting and polishing. The final cost of polished carats depends on usable rough, defect positions, geometry, the cutting plan, and actual yield.

Laboratory production can provide greater control over shape and planning than natural rough, but it does not eliminate the fundamental economic fact that grown weight and salable polished weight are not the same quantity.

HPHT Versus CVD Cost

There is no permanent rule that one method is always less expensive. Cost depends on size, target color and clarity, growth rate, equipment, energy economics, post-growth processing, failure rate, capacity utilization, and the geography of production.

Even when the market discounts one growth method at a particular time, that is a market pattern, not a physical law.

Factual Market Snapshot: Q2 2026

According to Edahn Golan, his LGD Wholesale Price Index in the second quarter of 2026 was approximately 13% lower than one year earlier and about 96% lower than at the start of the series in July 2018. The movement, however, was not the same across sizes: the 1.00 ct round segment in that series increased approximately 1% year over year, the 1.50–1.99 ct segment declined about 11%, and the 2 ct segment about 20%.

The most important part of this figure is its methodology. At the time, the series was based on cash transactions in Mumbai and Surat for IGI-graded laboratory-grown goods of better make, in small quantities, excluding shipping, insurance, and import duties. The index therefore must not be presented as the global retail price of all laboratory-grown diamonds.

Citing Tenoris POS data for U.S. specialty retailers, Edahn Golan reported for Q2 2026 that sales of laboratory-grown diamond jewelry increased by approximately 24%, while average expenditure remained relatively stable over approximately the preceding 18 months. This is therefore secondarily reported market data, not part of the methodology of his wholesale index. It illustrates an important market dynamic: a lower unit price may encourage the purchase of a heavier stone or a larger product without increasing the customer’s overall budget.

Why Prices Declined

The main structural reasons include technological learning, growth in production capacity, competition among growers and polishers, improved yield, standardization of commercial qualities, and greater offer transparency.

A laboratory-grown diamond is a technologically reproducible product. This does not mean that every stone is identical, but it does mean that scarcity does not behave in the same way as it does for natural geological material.

Wholesale and Retail Are Not the Same Graph

Wholesale prices may fall faster than retail prices. A retailer pays for more than the stone: inventory financing, premises, marketing, staff, returns, warranties, mounting, service, taxes, and the risk of inventory obsolescence.

A large difference between wholesale and retail price is therefore not automatic proof of an equally large net profit margin. Gross margin is not profit.

Conversely, a rapidly declining replacement cost can create inventory risk for a retailer: a stone purchased several months ago may be replaceable today at a substantially lower cost, so the old acquisition cost no longer determines market value.

Online, Physical, and Branded Retail

An online retailer may have lower display costs and less inventory but may pay for digital marketing, logistics, and returns. A physical store has a different cost profile. A brand may add value through design, service, reputation, and the purchasing experience.

Two offers for stones with the same laboratory specifications therefore need not have the same total price. Particularly in finished jewelry, the price of metal, workmanship, and design may become a more important part of the bill than the loose diamond itself.

Resale Does Not Have One Percentage

The secondary market may include a dealer cash bid, consignment, auction, private sale, or trade-in. Each channel has a different time horizon, cost, and risk.

Claims such as “laboratory-grown always loses 90%” or “it has no resale value” are therefore not professional without a defined transaction. A more realistic statement is: a rapid decline in new wholesale and retail prices puts intense pressure on secondary value, because the buyer of a used stone compares the offer with the current price of a new equivalent, not with the first owner’s original invoice.

A cash bid offered by a professional dealer today is not the same as a price that might be achieved after months of consignment or private sale.

Ask, Bid, and Realized Price

Ask is the requested price. Bid is the offered purchase price. The realized price is the actual transaction amount. An online listing is not proof that the stone sold at that price.

This principle is especially important in a rapidly changing LGD market, where publicly visible offers may lag behind the latest wholesale replacement cost.

Appraisal and Replacement Are Not Resale

An appraisal may serve different purposes and use different bases of value. Insurance replacement value estimates the cost of replacement under specific conditions; it is not a promise of how much the owner would receive from a sale. Fair-market or liquidation value also depends on definition, jurisdiction, market, and time horizon.

The detailed appraisal framework appears later in the book; one rule is sufficient here: every value figure must have a purpose and a date.

Laboratory-Grown as an Investment

A stone can have consumer, aesthetic, and sentimental value without being a good instrument for preserving capital. The rapid historical decline in LGD prices shows that the product must not be sold with an implicit promise of stable future value.

This is not the same as saying that resale must be zero. An individual outcome depends on the brand, design, stone, report, metal, sales channel, and current replacement cost.

What the Buyer Should Do

First, define the objective: wear and aesthetics or preservation of value. Then compare current like-for-like loose offers, understand what the additional retail price includes, verify the report and treatment status, and ask separately whether a genuine cash buyback or trade-in policy exists.

A “lifetime upgrade” is not the same as a cash guarantee. A “70%” discount is not informative if the initial reference price is arbitrary.

What the Retailer Should Monitor

For a professional, the key metrics are inventory age, replacement cost, sell-through, gross margin, markdown risk, and shifts in demand by size. In a market where new product prices are falling rapidly, slow-moving inventory may be a more important risk than the initial acquisition cost itself.

Chapter Summary

• The price of a laboratory-grown diamond is a market quantity, not a physical one.
• Production cost, wholesale, retailer cost, retail, appraisal, replacement, and resale are not the same.
• HPHT and CVD have different cost drivers, but neither method is universally less expensive.
• Rough output and polished output differ because of yield and manufacturing losses.
• Post-growth treatment, cutting, grading, and logistics add cost after growth.
• The Edahn Golan index for Q2 2026 was about 13% lower year over year and 96% lower than in July 2018, but it is a strictly defined wholesale series.
• Different sizes did not move equally in Q2 2026.
• A wholesale index must not be presented as a global retail price.
• A retailer’s gross margin is not the same as net profit.
• Resale has no universal percentage; the channel and current replacement cost are decisive.
• Appraisal and replacement value are not the same as cash resale value.
• A laboratory-grown diamond should be purchased with a realistic understanding that it is a technologically reproducible product whose future price cannot be guaranteed.

[VISUAL 55.1: Price chain—rough production → polished → wholesale → retailer cost → retail → secondary market]

[VISUAL 55.2: Q2 2026 LGD market snapshot—overall index and different behavior of the 1 ct, 1.5–1.99 ct, and 2 ct segments]

[VISUAL 55.3: Ask, bid, realized, appraisal, replacement, and resale—six different economic values]

[VISUAL 55.4: Inventory risk in a market with declining replacement cost—time, acquisition cost, new wholesale price, and markdown]