A 1.5 carat lab-grown diamond generally prices at a meaningful step up from a 1-carat stone of the same grade, not a proportional 50% increase, and consistently well below a natural diamond of comparable color and clarity. The exact figure still comes down to the same 4Cs (cut, color, clarity, carat) that price any diamond, but 1.5 carats sits at a size where rough-yield economics start to matter more than they do at 1 carat.
This guide fills the gap between our 1 carat lab-grown diamond price guide and 2 carat lab-grown diamond price guide, covering what specifically drives price at 1.5 carats, why this weight carries a disproportionate jump above 1 carat, how lab-grown pricing compares to natural at the same size, how CVD production trends have moved pricing over time, illustrative price ranges across color and clarity tiers, and practical sourcing guidance for jewelers stocking or quoting this weight.
What Drives 1.5 Carat Lab-Grown Diamond Pricing
Price at any carat weight is a function of the 4Cs interacting with each other rather than adding up independently — a shift in one factor changes the effective value of the others. At 1.5 carats, all four factors carry real, visible weight, and the table gets large enough that grading choices become slightly more consequential than they are at 1 carat:
| Factor | Effect on Price at 1.5 Carats |
|---|---|
| Cut | An Excellent or Ideal cut commands a real, visible premium over a Good or Fair cut at the same carat, color, and clarity — the larger table at 1.5ct makes a mediocre cut noticeably duller than the same flaw would be at 1 carat |
| Color | D-F (colorless) commands more than G-H (near-colorless), which commands more than I-J; at 1.5 carats, color differences are somewhat easier to notice than at 1 carat since more surface area is showing any body tint |
| Clarity | VS1-VS2 remains a common trade sweet spot at this size — eye-clean with meaningfully lower cost than VVS grades; SI1 can still be eye-clean, but warrants a closer stone-by-stone look than it would at 1 carat |
| Shape | Round brilliant commands the highest per-carat price of common shapes; fancy shapes typically run 15-30% less per carat at comparable quality |
See our 4Cs of diamonds guide and diamond pricing guide for a fuller breakdown of how these factors interact across carat weights generally.
Why 1.5 Carats Is a Meaningful Price Jump Above 1 Carat
The move from 1 carat to 1.5 carats is not a simple 50% price increase, even though it's only a 50% increase in weight. Rough-yield economics are the reason: cutting a well-proportioned 1.5-carat polished stone requires a meaningfully larger piece of rough than cutting a 1-carat stone, and larger rough crystals are both rarer to grow cleanly and slower to produce via CVD, since growth time and reactor capacity scale with size in a way that isn't linear. A grower gets fewer usable 1.5ct-plus crystals out of a given production run than 1ct-and-under crystals, and that yield curve shows up directly in the per-carat price a wholesale buyer sees quoted.
This is the same dynamic that drives the price jump from 2 to 3 carats and beyond, just at a smaller, earlier inflection point. A buyer comparing a 1-carat quote to a 1.5-carat quote at identical color, clarity, and cut should expect the per-carat price at 1.5 carats to run higher than the per-carat price at 1 carat — not just the total price, which rises for the obvious reason of more carat weight, but the rate itself.
1.5 Carat vs. 1 Carat vs. 2 Carat: Where It Fits
- 1 carat is the deepest, most liquid, and most price-transparent size in the trade, carrying a substantially lower total price than 1.5 carats at comparable color and clarity. Our 1 carat lab-grown diamond price guide covers that size in full.
- 1.5 carats reads as a genuine step up in visible presence over 1 carat without moving into the pricing and rough-scarcity dynamics that become more pronounced at 2 carats and above — a practical middle ground for a buyer who wants more size than 1 carat delivers but isn't ready for the price jump to 2 carats.
- 2 carats is the largest size most buyers still consider within reach of a standard bridal budget, with its own more pronounced rough-scarcity pricing dynamics. Our 2 carat lab-grown diamond price guide covers that size directly.
For a jeweler stocking a range of center-stone weights, 1.5 carats is worth carrying as a distinct tier rather than assuming customers will simply round to 1 or 2 carats — it fills a real gap in both visible size and price point, and buyers who specifically search for a 1.5-carat stone tend to know exactly why they want that weight rather than treating it as an approximation of something else.
Round Brilliant vs. Fancy Shapes at 1.5 Carats
| Shape | Relative Per-Carat Price vs. Round | Approx. Dimensions at 1.5ct |
|---|---|---|
| Round brilliant | Baseline (highest) | ~7.4mm diameter |
| Oval | 15-20% less | ~9.7mm × 6.9mm |
| Cushion | 15-20% less | ~7.1mm × 7.1mm |
| Emerald | 20-25% less | ~8.0mm × 5.9mm |
| Pear | 20-25% less | ~9.9mm × 6.6mm |
| Marquise | 20-30% less | ~12.0mm × 6.0mm |
Round brilliant's premium at 1.5 carats reflects both higher rough wastage during cutting — a round wastes more of the original crystal than most fancy shapes — and consistently higher demand. For a buyer stretching a 1.5-carat budget, elongated shapes like oval, pear, and marquise deliver noticeably more visible surface area per carat than round at a lower per-carat cost, a two-sided value proposition worth walking a customer through directly. Our marquise diamond guide covers this elongation effect in more depth.
What Certification Adds to the Price
At 1.5 carats, certification is close to universal in the trade-quality segment of the market — the value at stake is high enough that buying uncertified goods at this weight represents a meaningful, largely unnecessary risk relative to the modest savings involved. A certificate from an independent lab is what lets a buyer, and their eventual customer, verify the 4Cs independently rather than taking a seller's word for it.
- IGI is the most common certifying lab for lab-grown diamonds specifically, with strong international trade recognition.
- GIA carries the strongest overall trade and consumer name recognition across both natural and lab-grown, often commanding a modest premium reflecting that recognition.
- GCAL is known for particularly rigorous light-performance and cut-grade analysis, a differentiator some buyers specifically seek out given how visible cut quality becomes on a 1.5-carat table.
Lab-Grown vs. Natural: 1.5 Carat Price Comparison
The price gap between lab-grown and natural diamonds widens as carat weight increases, and 1.5 carats already shows a clearly wider gap than 1 carat, though not yet as dramatic as the gap at 2 carats and above. Natural rough capable of yielding a well-proportioned 1.5-carat polished stone is scarcer than the rough that yields 1-carat stones, while CVD production scales with manufacturing capacity rather than being constrained by what a given mine happens to produce at that size. A natural 1.5-carat diamond of a given color and clarity grade will typically price at a substantial multiple of a lab-grown stone at the identical grade — the exact multiple varies by supplier and market conditions and has narrowed somewhat as lab-grown production has scaled, but the gap remains large and substantive.
This is a structural cost difference, not a quality difference: natural pricing at 1.5 carats reflects geological rarity and mining cost, while lab-grown pricing reflects CVD production time, equipment, and energy cost. For a retailer positioning a 1.5-carat piece, that gap is one of the more persuasive value arguments for lab-grown at this specific size, since a buyer can access noticeably more carat weight and higher color/clarity grading for a given total budget than natural would allow. Our lab-grown diamond guide covers the CVD growth process in more depth.
Illustrative Price Ranges by Color and Clarity at 1.5 Carats
Exact pricing depends on a specific supplier, a specific stone's certificate, and current market conditions — the ranges below are general market education, not a live GuruDiam price list, and are meant to illustrate roughly how the market prices different grading combinations relative to each other at this weight, not to quote an exact figure for any individual stone:
| Quality Tier | Color / Clarity Combination | Typical Cut Grade | Illustrative Wholesale Range (1.5ct, per stone) |
|---|---|---|---|
| Value tier | I-J color, SI1-SI2 clarity | Good-Very Good | Roughly $1,800-$2,400 |
| Trade sweet spot | G-H color, VS1-VS2 clarity | Very Good-Excellent | Roughly $2,600-$3,400 |
| Upper-mid tier | G-H color, VVS1-VVS2 clarity | Excellent | Roughly $3,200-$4,200 |
| Premium tier | D-F color, VS1-VS2 clarity | Excellent-Ideal | Roughly $3,800-$4,800 |
| Top tier | D-F color, VVS1-VVS2 clarity | Ideal | Roughly $4,800-$6,500 |
Read this table as a general shape of the market rather than a fixed number: a typical 1.5-carat CVD lab-grown diamond in the G-H color, VS clarity range might be quoted in roughly the $2,600-$3,400 range by a given wholesale supplier at a given moment, with premium pricing for D-F color paired with IF-VVS clarity, and lower pricing for I-J color and SI clarity. Actual quotes will vary supplier to supplier and move with the broader lab-grown market, so treat any specific number here as illustrative rather than a quote to hold a supplier to.
Most retail volume at 1.5 carats concentrates in the trade sweet spot and upper-mid tiers, since both deliver a stone that reads eye-clean and near-colorless to the naked eye at a meaningfully lower cost than the top tier — a distinction worth walking a retail customer through directly rather than assuming they'll default to paying for the highest available grade.
How CVD Production Has Moved 1.5 Carat Pricing Over Time
Lab-grown diamond pricing at 1.5 carats has trended downward over the past several years, following the same broad pattern seen across the CVD market generally as production capacity has scaled and reactor technology has matured. This decline reflects manufacturing efficiency and expanding supply rather than any change in stone quality — a well-cut, well-graded 1.5-carat CVD stone today is not a lesser product than one produced several years ago, it simply costs less to produce at scale than it did when the industry's production capacity was smaller.
For a jeweler who's stocked lab-grown inventory for a few years, this trajectory means cost basis and retail pricing both warrant periodic review rather than an assumption that figures from a year or two ago still hold. The pace of this decline has not been perfectly uniform across every size — larger, harder-to-grow rough has generally seen slower proportional declines than smaller, more commoditized sizes — but the overall direction across the market has been consistently downward as production has scaled. A buyer newer to lab-grown sourcing should confirm current pricing directly with a supplier rather than working from an older reference point, since the gap between "current" and "a year old" can be meaningful at this size.
What Actually Sits Behind a 1.5 Carat Wholesale Quote
A wholesale quote for a 1.5-carat lab-grown stone reflects several stacked cost components rather than a single number: the rough crystal itself, CVD growth time and equipment cost, cutting and polishing labor, independent lab certification, and the supplier's own margin. Cutting and polishing specifically is a skilled, labor-intensive step, and much of the trade's CVD cutting and polishing work — including Guru Diam's — is done in India before the finished stone is graded and shipped from a US location. That's a normal, standard part of how the diamond supply chain is structured today, and it's worth understanding as one factor in why a 1.5-carat stone's price stack looks the way it does, alongside rough cost, growth time, and certification.
Understanding this stack is useful for a buyer evaluating whether a quote is reasonable: a price that seems unusually low relative to the ranges above is worth a closer look at what's actually being represented — cut grade, certifying lab, and whether the stone has been independently verified — rather than assumed to simply be a better deal.
Common Buyer Mistakes When Shopping by Price Alone
- Comparing quotes without confirming identical grading. A lower price often simply reflects a lower color, clarity, or cut grade rather than a genuinely better deal — any price comparison needs to hold the 4Cs constant to be meaningful.
- Assuming 1.5 carats costs 50% more than 1 carat. Per-carat pricing rises with size due to rough-yield economics, so a 1.5-carat stone at the same grading combination typically costs more than a straight 50% increase over the equivalent 1-carat price.
- Ignoring cut grade entirely. Color and clarity get the most attention, but a poorly cut stone can look visibly duller across a 1.5-carat table than the same flaw would on a smaller stone — cut grade should never be the line item skipped to save cost.
- Not verifying certification independently. A certificate number should be checked against the issuing lab's own database, not simply taken at face value from a seller's paperwork.
- Working from outdated price references. Given how much lab-grown pricing has moved as CVD production has scaled, a figure from even a year or two ago may no longer reflect what a current supplier will actually quote.
How to Read a 1.5 Carat Diamond Quote
| Line Item | What to Check |
|---|---|
| Certification | Which lab, and whether the report number is verifiable through the lab's own lookup tool |
| Growth method | CVD should be clearly stated; HPHT origin should never be ambiguous or undisclosed |
| Cut grade | Listed separately from color and clarity — a stone can carry strong color and clarity grades but a mediocre cut grade that undercuts visible brilliance on a 1.5-carat table |
| Measurements | Actual millimeter dimensions confirm the stone matches its stated carat weight proportionally rather than being cut unusually deep or shallow to hit a target weight |
| Fluorescence | Strong fluorescence can modestly reduce price relative to a non-fluorescent stone of the same grade — worth confirming via video or in-person review rather than assuming it affects appearance |
1.5 Carat Lab-Grown Diamonds in Popular Settings
How a 1.5-carat stone is set meaningfully affects both its perceived value and the total budget a buyer is working within, worth factoring into a pricing conversation alongside the stone's own grading:
- Solitaire settings let a 1.5-carat stone stand entirely on its own — a genuinely popular choice at this size, since the weight itself already carries visible presence without needing a halo or accent detail to read as substantial. See our solitaire setting guide.
- Three-stone settings pair a 1.5-carat center stone with two side stones, a popular configuration for buyers who want a center stone with real presence flanked by meaningful accent weight rather than small melee — this changes the total stone budget calculation beyond the center stone price alone, since the side stones are typically certified or near-certified quality themselves at this scale rather than parcel melee.
- Halo settings can make a 1.5-carat center stone read visibly larger, a common choice for buyers wanting to maximize apparent size within a set budget without moving up to a 2-carat center stone.
- Hidden halo settings — see our hidden halo ring guide — add a similar size boost with a more subtle presentation than a traditional visible halo.
A buyer working within a fixed total budget often benefits from understanding these tradeoffs explicitly: a slightly lower center stone grade paired with a halo or three-stone setting can deliver comparable visual impact to a higher-grade solitaire at a similar total price, a genuinely useful framing for a sales conversation built around value rather than grade alone.
Inventory and Sourcing Considerations for Jewelers Stocking 1.5 Carats
1.5 carats is a less commonly stocked weight than 1 carat, which means inventory depth across the trade generally is thinner and lead times on a specific grading combination can run longer than they would at 1 carat. For a jeweler building out a stocking program, this argues for holding a smaller, more curated selection of 1.5-carat stones across the most commonly requested combinations — G-H/VS being the clearest example — rather than trying to match the same depth of selection carried at 1 carat. Custom or made-to-order sourcing for a specific 1.5-carat grading combination outside that core range is generally more practical than trying to hold every possible combination in stock, given how much thinner the inventory pool gets at this weight relative to 1 carat.
Because 1.5 carats sits between two much more heavily traded weights, it's also worth confirming a supplier's actual current inventory at this specific size before quoting a customer a firm delivery timeline — a supplier that's deep in 1-carat and 2-carat stock isn't necessarily equally deep at 1.5 carats, and that gap is worth checking directly rather than assuming.
Comparing Quotes Across Multiple Suppliers
When evaluating quotes from more than one wholesaler for a 1.5-carat stone, the most reliable comparison holds every variable constant except price: same shape, same color grade, same clarity grade, same cut grade, and the same certifying lab. Even small differences in any one of these — a G versus an H color, a VS2 versus an SI1 clarity, an Excellent versus a Very Good cut — can account for a meaningful price gap on their own, independent of whether one supplier is simply offering a better deal. Requesting quotes on a specific, fully-specified stone, down to the certificate number where a supplier has one in hand, removes ambiguity from the comparison and makes any remaining price difference genuinely meaningful rather than an artifact of comparing two subtly different stones. It's also worth confirming shipping timeline and cutoff terms alongside price, since a modestly higher price from a supplier with reliable same-day shipping can be the better overall deal for a jeweler working against a customer's timeline.
Sourcing 1.5 Carat Lab-Grown Diamonds at Wholesale
Guru Diam supplies certified CVD lab-grown diamonds — no HPHT anywhere in the catalog — with IGI, GIA, and GCAL certification all available, across round brilliant and the full range of fancy shapes. In-stock 1.5-carat inventory ships same-day from New York (before 6pm EST) and Los Angeles (before 4pm PST), which is worth confirming directly given how much thinner trade inventory generally runs at this weight compared to 1 carat.
Buyers can browse current 1.5-carat inventory through the certified diamonds category, and buyers building a full piece around a 1.5-carat center stone — solitaire, halo, or three-stone — can work through custom jewelry for a setting finished in 4-6 days. For fancy-color center or accent stones at this weight, the fancy color loose diamonds category and matching pairs category cover side-stone sourcing for a three-stone build. For buyers weighing this size against adjacent weights, our 1 carat lab-grown diamond price guide and 2 carat lab-grown diamond price guide cover how price and visible size scale in both directions. Trade accounts can review terms at the wholesale hub or apply through trade partner.
Frequently Asked Questions
How much does a 1.5 carat lab-grown diamond cost?
Price varies significantly by cut, color, clarity, shape, and certifying lab, but as a general market range, wholesale quotes for a 1.5-carat CVD lab-grown diamond commonly run from roughly $1,800 at the value end (I-J color, SI clarity) up to $6,000 or more at the top end (D-F color, VVS-IF clarity). Getting an accurate figure for a specific purchase requires pricing a specific combination of the 4Cs with a supplier directly rather than relying on a single blanket number.
Is a 1.5 carat lab-grown diamond 50% more expensive than 1 carat?
No — per-carat pricing rises with size due to rough-yield economics, so a 1.5-carat stone at the same grading combination typically costs more than a simple 50% increase over the equivalent 1-carat price. The jump reflects both the added carat weight and a higher per-carat rate at the larger size.
Why is a 1.5 carat lab-grown diamond so much cheaper than natural?
Lab-grown pricing reflects CVD production cost — equipment, energy, and growth time — which scales with manufacturing investment, while natural diamond pricing reflects geological rarity and mining cost. Those are fundamentally different cost structures, not a quality difference between the two, and the gap between them is already substantial at 1.5 carats.
What shape is cheapest for a 1.5 carat lab-grown diamond?
Round brilliant commands the highest per-carat price of common shapes due to higher rough wastage during cutting and consistently strong demand. Elongated fancy shapes like oval, pear, and marquise typically price 15-30% lower per carat while also appearing larger face-up at the same weight.
What color and clarity should I choose for a 1.5 carat lab-grown diamond?
G-H color with VS1-VS2 clarity is a common trade sweet spot at this size — near-colorless and eye-clean at a meaningfully lower price than top D-F/VVS combinations that are difficult to distinguish without magnification, even on a 1.5-carat table.
Has lab-grown diamond pricing gone down over time?
Yes — lab-grown pricing across sizes, including 1.5 carats, has generally trended downward as CVD production capacity has scaled and matured. This reflects manufacturing efficiency, not a change in stone quality, and it's worth confirming current pricing with a supplier rather than working from an older reference figure.
