Original Data · From Our Live GIA Stock · Real Prices
What a diamond costs per carat in South Africa, from our own stock.
Price per carat is not a number, it is a curve, and the bigger the stone the more you pay on every carat of it. Most sites quote a textbook figure. We can show you the real one, computed live from the priced GIA-certified diamonds we actually hold.
Across our current priced stock the median works out near R27 200 per carat, but that blends every size. Split by size band, the curve, and where it jumps, is the useful picture.
-
Natural diamonds only
Mined-Earth, never lab-grown, by conviction, not price. Kimberley-Process documented from the mine of origin. Why we don’t sell lab-grown →
-
GIA & EGL certified
Every loose stone certified by the GIA or EGL. Cert PDF supplied per stone.
-
Insured delivery, SA & worldwide
Overnight across South Africa via Brink’s, G4S or our nominated jewellery courier. Insured worldwide dispatch via Ferrari Group and FedEx Custom Critical.
-
14-day in-person exchange
In-person sales at the viewing room come with a 14-day exchange courtesy on stock pieces. Distance-sale CPA cooling-off applies.
The real per-carat curve, by size band
Each bar is the median price per carat of the priced stones we hold in that size band. It is computed from live stock, so it moves as diamonds sell and new ones are cut. The shape is the thing to read: the rate you pay per carat climbs with size, and steps up hardest as a stone crosses one carat.
The numbers, and the one-carat jump
The table is the same data in full. Look at the move from the sub-one-carat bands to the one-carat band: the per-carat rate more than doubles, because rough large enough to cut a clean one-carat stone is so much scarcer. That single step is the most expensive on the whole curve, and it is why a half-carat is so much keener per carat than a full carat, and why buying just shy of a round weight saves real money.
| Carat band | Stones | Median price / carat | Median total |
|---|---|---|---|
| 0.30 to 0.49 ct | 23 | R19 039 | R7 806 |
| 0.50 to 0.99 ct | 25 | R28 560 | R20 155 |
| 1.00 to 1.49 ct | 14 | R82 280 | R87 394 |
| 1.50 ct and up | 5 | R102 000 | R211 140 |
Stock currently spans 0.24 to 2.07 carats. A band blends different colour and clarity grades, so it shows the shape of the market, not a quote. Your exact stone is priced on its own four Cs, firm and in writing.
What the curve means for your budget
Read this curve before you fix a number, because size is where most of the money goes and where the easiest savings hide. Three honest moves fall straight out of it:
- Buy just shy of a round weight. The per-carat rate steps up at the round numbers, so a 0.90 or 1.90 carat looks identical face-up to the round figure but sits a notch down the curve. We usually hold a few of these shy weights.
- Weigh size against the per-carat jump. Crossing one carat more than doubles the per-carat rate. If size matters most, go in with that open-eyed; if value matters most, a strong sub-carat stone is often the smarter buy.
- Protect cut, not weight. A well-cut shy stone faces up larger than a deep, badly cut heavier one, so cut quality can buy you apparent size for less than another tenth of a carat would.
That is the practical reason we publish our own numbers rather than a generic table: you can see the real curve, then open the actual stones it is built from on our loose-diamond stock and ask us to price any of them firm.
Where this data comes from
Every figure here is computed from the priced, GIA-certified loose diamonds Prodiam actually holds in stock, the same stones you can open and buy on our loose-diamond pages. We use the median rather than the average so one unusual stone cannot skew a band, exclude price-on-application stones from the price maths, and recompute on each update as stock sells and new stones are cut. It is real inventory, not a third-party index or an estimate. As a cutting house that buys rough at De Beers viewings and cuts in-house at Procut DCW, the prices are at the cutter-direct level, before the importer and retail margins a counter would add. For the mechanism behind the rand figures, see how diamonds are priced in South Africa, and for how the rand and the dollar have moved those prices over time, see diamond price trends.
Diamond price per carat: common questions
How much is a diamond per carat in South Africa?
There is no single per-carat figure, because the price per carat rises steeply with the size of the stone, and we can show you that from our own stock rather than a textbook. Across the priced GIA-certified diamonds Prodiam currently holds, the median price works out near R27 200 per carat, but that blends every size together.
Broken into bands it is far more useful: a stone in the 0.30 to 0.49 carat range runs around R19 039 per carat, while the largest stones we hold run around R102 000 per carat, because rough that yields a large clean stone is far scarcer.
So the honest answer is that per-carat price is a curve, not a number, and the bigger the stone the higher the rate you pay on every carat of it.
Why does the price per carat go up as the diamond gets bigger?
Because large rough is disproportionately rare. A diamond crystal big and clean enough to yield a well-cut two-carat polished stone is far scarcer than the rough behind a half-carat, so the market charges more for each carat at larger sizes, on top of the extra weight. The two effects compound, which is why a two-carat diamond costs several times a one-carat of the same grades rather than double.
Our own stock shows the curve plainly: the per-carat figure more than doubles between the under-one-carat bands and the one-carat-plus bands, then keeps climbing. It is the single most important thing to understand before you set a budget by size.
Is it cheaper per carat to buy a smaller diamond?
Yes, markedly. The smaller the stone, the lower the price per carat, which is why two half-carat stones cost far less than one full-carat stone even though they weigh the same in total. In our stock the sub-half-carat band sits at a small fraction of the per-carat rate of the largest band.
This is the logic behind a few sensible value moves: buying just shy of a round weight, where a 0.90 or 1.90 carat looks identical to the round number but sits a step down the curve, and choosing the size honestly against what the per-carat jump costs you. We will always show you where the curve turns for your budget.
Are these real Prodiam prices or an estimate?
These are real. The figures on this page are computed directly from the priced, GIA-certified loose diamonds Prodiam actually holds in stock, the same stones you can open and buy on our loose-diamond pages, not a third-party index or a made-up table. We use the median rather than the average so a single unusual stone cannot skew a band, and we exclude price-on-application stones from the price maths.
Because it reads from live stock, the curve updates as stones sell and new ones are cut. One honest caveat: a band blends stones of different colour and clarity, so it shows the shape of the market, not a quote, your exact stone is always priced on its own four Cs.
What is the cheapest carat weight that still looks like a full carat?
A stone just below a round weight, because the per-carat price steps up hardest at the round numbers buyers ask for.
A 0.90 to 0.95 carat round brilliant is within a fraction of a millimetre of a full carat face-up, yet it sits below the one-carat threshold where the per-carat rate jumps, so it can be quietly and meaningfully cheaper for a look no one will tell apart on the hand. The same trick works at 1.90 against 2.00 carats.
Our stock usually carries a few of these shy weights at any time, and they are among the first stones we point value-minded buyers to.
Computed from Prodiam live stock and last verified by Darren Etkind, director, Prodiam Trading, on 26 June 2026. Figures are real asking prices for in-stock GIA-certified diamonds; a band median blends grades and is not a quote for a specific stone.