Diamonds Are Marketed as an Investment. Here's What the Resale Data Actually Shows
7 min read
Loading...
7 min read
You just paid for a diamond ring. Walk back into that same shop tomorrow and ask what they will give you for it, and the number will be far below what you paid, sometimes by half or more. That gap is not a scam and it is not bad luck. It is how the diamond market actually works, and the data behind it is public if you know where to look. This is what the real diamond resale value data shows, and what it means if you already own one and are tracking it as part of your net worth.
A diamond's retail price is not just "the diamond." It includes the jeweller's cost of the stone, plus their margin, the cost of the setting, marketing, rent and staff. When you resell, none of that transfers. A buyer only pays for the stone and metal itself, at wholesale.
Traditional jewellery pricing uses keystone, meaning the retail price is roughly double the wholesale cost, and markups of 2 to 3 times wholesale are standard across the industry, higher still on smaller, cheaper pieces (a pattern confirmed across multiple jewellery-industry pricing guides). Trade publication JCK Online reported in 2026 that even as wholesale prices for lab-grown diamonds have collapsed, retailers have kept capturing a markup of more than 80% above wholesale, a figure that has barely moved in a year (JCK Online, "Lab-Grown Diamond Wholesale Prices Are in Freefall; Retail Margins May Be Next," retrieved 2026-08-16). The retail markup does not shrink just because the stone itself is worth less. That is the first reason a resale offer looks so low next to the receipt.
Professionals in the diamond trade do not price stones off a shop window. They use the Rapaport Diamond Price Index (RAPI), a wholesale benchmark tracking round diamonds by the 4Cs (cut, colour, clarity, carat) that has been the industry reference for decades.
That index has been falling. Rapaport's own reporting put the overall 2025 decline for 1-carat natural diamonds at 11.3%, with the 1-carat SI-clarity segment down a sharper 24.1% over the same year. Into early 2026, the slide continued at a more moderate pace: RAPI for 0.30- and 1-carat stones fell a further 1.3% in January, the 0.50-carat segment fell 1.2%, and 3-carat stones slid 1.6% (Rapaport, "Decline in Diamond Prices Eases," press release, retrieved 2026-08-16).
Not every diamond behaves the same way. Very large, rare or fancy-coloured stones can trade in a genuinely different, collector-grade market and have held or grown in value in specific cases. That is the exception behind the headlines, not the everyday engagement-ring stone this data covers.
If you bought a lab-grown diamond instead of a natural one, the resale math is worse, not better. Lab-grown stones are manufactured, not mined, so as production capacity expanded, wholesale prices did not just soften, they collapsed.
StoneAlgo's own lab-grown diamond price index put the average 1-carat lab-grown stone at roughly $3,410 in 2020. By May 2026 that same index averaged $564 a carat, a decline of about 83% (StoneAlgo index data, retrieved 2026-08-16; the percentage is this article's own arithmetic on StoneAlgo's two published figures, not a number StoneAlgo itself states). JCK Online reported the wholesale cost to produce a 1-carat lab-grown diamond had fallen below $150 by the first quarter of 2026, the underlying reason the resale price cannot hold up (JCK Online, retrieved 2026-08-16).
A lab-grown stone is not scarce the way a mined one is, and a resale buyer is not paying for the certificate, the marketing or the story behind it. They are paying whatever that carat weight costs to produce today, and that cost keeps falling.
Search "jual kembali berlian" and the honest answer from Indonesian jewellers themselves is that you are not really selling into an open market. You are usually trading into a buyback or trade-in program run by the same shop that sold it to you, priced off your own invoice, not off today's market.
Jakarta jeweller MyJewel states plainly on its own buyback and trade-in policy page that selling diamond jewellery back to them means a 30% deduction from the invoice value, the price you paid, not the item's current worth (MyJewel, "Panduan Buy-Back, Trade-In & Deposit," retrieved 2026-08-16). Diamond & Co runs a narrower, more generous-looking program: trade in a certified natural diamond piece within 30 days of purchase and the exchange value is 100% of the invoice price, but only as credit toward a different piece from the same store, not cash, and not available while an instalment plan is still unpaid (Diamond & Co, "Prosedur Penjualan Kembali dan Tukar Tambah," retrieved 2026-08-16). Passion Jewelry's own procedure page states its resale and trade-in percentages are calculated against the original sale invoice, excluding VAT, the same structure (Passion Jewelry, "Prosedur Penjualan & Tukar Tambah," retrieved 2026-08-16).
Say you buy a certified 1-carat natural diamond ring for Rp60,000,000 at a Jakarta jeweller. This is a hypothetical, not a real transaction:
| Scenario | What you would get | Basis |
|---|---|---|
| Trade in within 30 days, same store, as store credit | Rp60,000,000 (100%) | Diamond & Co's own published trade-in policy |
| Sell back to the same store after that window | Roughly Rp42,000,000 (70%) | MyJewel's own 30% buyback deduction |
| Sell to an unrelated jeweller, no relationship to the original sale | Priced off the wholesale stone value only, commonly well under half the original retail price | RAPI wholesale index plus standard 2 to 3x retail markup |
The number that actually matters is the one in the third row, because it is the only one available to someone who does not still have a relationship with the original seller, or wants cash rather than another piece of jewellery.
Not in the way the word "investment" usually implies. An investment is something you buy expecting to sell later for more than you paid, ideally through a market with real buyers and visible prices. A diamond ring does not have that: no exchange, no daily quote, and a retail markup that never transfers to you as the seller. What it does have is real value as jewellery to wear and, often, sentimental value that has nothing to do with resale price. Those are legitimate reasons to buy one. "It will hold its value" is not one of them, on the data above.
If a diamond is already sitting in your portfolio as a manual asset, the honest move is to value it at what you would actually get back, not what the receipt says. On NetWort's Holdings page, luxury goods like jewellery default to a Standard sub-category with a -15% annual rate assumption, distinct from the Collectible sub-category (used for pieces like a sought-after Rolex) which defaults to +5% a year. A diamond ring you did not buy from a specialist collector's market almost always belongs in Standard, not Collectible, and the rate you enter should reflect a realistic buyback or resale figure like the ones above, not the original invoice.
The same quoted-value-versus-real-cash gap shows up across watches, art and other collectibles, not just diamonds. Our breakdown of collectibles and liquidity risk has the comparable spread data for those categories. Gold is the one physical asset that mostly escapes this problem, with an active resale market and a visible spot price; see how physical gold's own round-trip spread compares if you are weighing it against jewellery as a store of value.