The Retailers Charging You Double and the Ones Saving You Thousands

Someone is paying 167% more for the same diamond

That's not a typo. Across the 42 million diamond listings we track from 110+ retailers, the price spread on identical stones is genuinely extraordinary. A 1.5ct lab-grown radiant that costs $800 at one retailer sits at $2,800 at another. Same certificate number. Same stone. Different price tag.

We've been building CaratHunter's cross-retailer matching system for months now, and the pattern is consistent: where you buy matters as much as what you buy. Sometimes more. The retailer markup gap dwarfs the difference between, say, a VS1 and a VS2 clarity grade. And yet most buyers spend hours agonising over specs while never checking whether their chosen retailer is competitive.

That changes today. We pulled the numbers on price leadership, average markups, inventory depth, and unique selection across every retailer in our system. Some of these results will make you rethink where you shop.

Who's actually competitive

Price leadership measures how often a retailer offers the lowest price for a given diamond specification. A score of 100% means they're never beaten on price in their categories. But that number alone doesn't tell you everything, because a retailer with 600 listings competing in a narrow niche will look different from one with 136,000 listings spanning the full market.

Here's how the top retailers stack up:

Retailer	Active Listings	Avg Markup	Price Leadership	Unique Inventory
Blue Nile	29,380	-12.5%	100%	100%
Lukhi Diamond	954	-15.0%	100%	99.4%
Grown Brilliance	24,096	+28.4%	100%	100%
James Allen	136,399	+53.4%	100%	100%
Temple and Grace	690	+167.5%	100%	100%

Two retailers jump out immediately. Blue Nile and Lukhi Diamond are pricing below market averages, with Lukhi running a consistent 15% discount and Blue Nile at 12.5% under. For buyers focused purely on price, these are the places to start.

But the 100% price leadership across the board needs context. Both Blue Nile and James Allen carry entirely unique inventory, meaning their stones aren't cross-listed with other retailers. When you're the only one selling a specific diamond, you're always the cheapest (and the most expensive) by default. Price leadership matters most where the same stone appears at multiple retailers, which is where our cross-retailer analysis becomes essential.

James Allen, despite a 53% average markup, remains one of the most popular retailers in the world. That premium buys you the largest selection we track (136,399 active listings), excellent imagery, and a polished buying experience. Whether that experience is worth paying half again as much per carat is a question every buyer should answer with numbers, not brand loyalty.

And then there's Temple and Grace. At 167.5% above market, they're in a category of their own. With only 690 listings, they're a small Australian jeweller charging boutique premiums. If you're buying from Temple and Grace, you're paying for the local experience and customer service. Just know that you're likely paying more than double what the same spec would cost elsewhere.

Lab-grown is where the real pricing chaos lives

The natural diamond market has its markups, but lab-grown is where retailer pricing gets wild. Average lab-grown prices sit at $1,193 compared to $7,534 for natural stones, a gap of roughly 84% across shapes. But the spread between retailers on identical lab-grown diamonds is where buyers leave serious money on the table.

Shape	Avg Cross-Retailer Match %	Avg Price Spread
Round	62.4%	214%
Radiant	49.1%	254%
Emerald	48.6%	242%
Oval	47.8%	216%
Heart	51.2%	194%
Cushion	46.6%	214%
Pear	45.1%	227%
Marquise	48.0%	190%
Princess	47.2%	201%
Asscher	53.2%	185%

A 254% average spread on lab-grown radiants means the most expensive retailer is charging roughly 3.5 times what the cheapest retailer charges for the same stone. Rounds show a 214% spread with 62% of inventory appearing at multiple retailers, making them the easiest shape to comparison shop.

These aren't theoretical numbers. If you're buying a 2ct lab-grown emerald cut and you don't check at least three retailers, you could easily overpay by $1,500 to $2,000. The stones are physically identical. The certificates match. Only the price is different.

Grown Brilliance, despite being marked as a price leader, carries a 28% markup on its lab-grown inventory. That positions them in the middle of the pack. For lab-grown specifically, the savings from cross-retailer shopping absolutely dwarf any loyalty discount or promotional offer a single retailer can match.

The natural to lab-grown gap by shape

Buyers still choosing between natural and lab-grown should pay attention to where the price gap is widest. The overall gap sits at about 84%, but it varies meaningfully by shape.

Marquise shows the largest gap at 87.8%. A natural marquise averages $8,017 compared to $978 for lab-grown. That's an eight to one ratio. If you love the marquise shape and don't have strong feelings about origin, lab-grown is an absurdly good deal right now.

Princess cuts show the smallest gap at 77.9%, followed by rounds at 79.8%. Natural princess cuts average $5,110 compared to $1,127 for lab-grown. Still a massive difference, but notably tighter than other shapes. Rounds are the most commoditised shape in both markets, so the tighter gap reflects more efficient pricing.

Square radiants are interesting outliers at 71.1%, though the natural average of $1,500 is unusually low, likely reflecting thinner inventory in that specific cut.

For buyers on a budget who want maximum visual impact, a lab-grown marquise or pear (86.7% gap) delivers the most carat weight per dollar. A $1,000 lab-grown marquise buys you a stone that would cost $8,000 in natural. That freed up $7,000 can buy a significantly better setting.

What's moving this week

Natural diamond prices ticked up 25 points on our 7-day index, while lab-grown moved just 4 points. The 30-day picture is more telling: natural is up 6.6 points, while lab-grown is essentially flat at -0.6. Two markets moving at different speeds.

The big movers are all in high-carat natural stones, which makes sense given the thin inventory at those weights:

Category	7-Day Price Move (per carat)	Listings
Natural Asscher 5 to 10ct D-E VVS	+$2,325	38
Natural Marquise 5 to 10ct F-G VS	+$2,194	45
Natural Round 4 to 5ct D-E VVS	+$1,722	630
Natural Oval 5 to 10ct D-E VVS	+$1,691	146
Natural Oval 4 to 5ct D-E VVS	+$1,618	69

These are all trophy stones. Five carat plus, top colour, top clarity. With only 38 listings for natural asscher cuts in that range, a few high-priced additions can swing the median significantly. The round 4 to 5ct category is more liquid at 630 listings, so that $1,722 per carat move carries more weight.

No categories showed significant 7-day price drops, which is unusual. That suggests steady demand across the board, or at least no panic selling.

On the supply side, lab-grown round 1.5 to 2ct listings exploded by 2,600% this week. That's the engagement ring sweet spot, and the flood of new inventory should put downward pressure on prices in the coming weeks. Buyers in that category might benefit from waiting a fortnight.

Where to actually shop

Stop thinking about retailers as brands and start thinking about them as pricing tiers. Your shopping strategy should depend entirely on what you're buying.

If you're buying natural, 1 to 2 carats, round or oval: Blue Nile's 12.5% below market average makes them the obvious starting point. Their inventory is unique (not cross-listed), so you won't find the exact same stone cheaper elsewhere. But you should still compare specs and prices against competitors to verify their pricing holds up in your specific category. Use our advanced search to run that comparison in seconds.

Buyers should also consider Lukhi Diamond for natural stones. Their -15% average markup is the deepest discount we track. The inventory is smaller at 954 listings, but if they carry what you're looking for, you're likely getting the best price available.

If you're buying lab-grown, any shape: Cross-retailer shopping is non-negotiable. With average spreads of 190% to 254% on identical stones, buying from a single retailer without checking others is like paying sticker price on a car. Grown Brilliance has strong selection at 24,096 listings, but their 28% markup means you should always verify the price. Our cross-retailer comparison flags the exact same certified stone at different retailers with the price gap calculated for you.

If you want a fancy shape (marquise, pear, heart): Lab-grown pricing gaps are widest here, 86% to 88% below natural. And cross-retailer spreads are still 190% to 227%, so shopping around saves hundreds. These shapes also tend to face up larger than rounds of the same carat weight, so you're getting more visual size for less money.

If you're in Australia: Temple and Grace's 167% markup is hard to justify on price alone, even accounting for the currency conversion and local service. Diamond Imports and GS Diamonds offer local options without that premium. If supporting an Australian jeweller matters to you, at least know the cost of that choice.

The exceptional finds right now

Our market signals flagged several stones worth noting this week. Two natural princess cut diamonds at 1.51ct D colour are sitting at $2,030 and $2,410, which is 80% to 83% below the median price per carat for that category. The median for natural 1.5 to 2ct princess sits at $7,823 per carat. At $1,344 per carat, that $2,030 stone is either a data entry error or a genuine outlier. Either way, it's worth investigating if princess is your shape.

On the lab-grown side, a 0.45ct F colour round at $187 sits 70% below the median for its category. Small stones like this are often overlooked, but for accent stones or cluster settings, that's a steal. You can browse these and other exceptional values through our deal finder.

What we're watching next

That 2,600% supply spike in lab-grown 1.5 to 2ct rounds is the biggest story developing. If that inventory sticks around (and doesn't get delisted within the week), prices in the most popular engagement ring category should soften. We'll be tracking whether retailers absorb the new supply at current prices or start cutting to move volume.

Natural cushion supply also jumped, with 0.5 to 0.75ct cushions up 2,467% and 1 to 1.25ct up 1,583%. Cushions have been gaining popularity as a round alternative, and more supply generally means better deals for buyers.

The high-carat natural market (4ct plus) is running hot with no categories showing price declines. That could signal genuine scarcity at the top end, or it could be a temporary blip driven by a few new high-priced listings. We'll know more in a fortnight.

Meanwhile, the fundamental truth hasn't changed: the retailer you choose matters more than almost any spec decision you'll make. A VS2 from a competitive retailer beats a VVS2 from an overpriced one, every single time. Shop the market, not the brand.