The loose lab grown diamond market in the USA has shifted faster in the last three years than almost any other category in the jewelry trade. Lab grown diamonds now represent over 55% of engagement ring center stones sold in the US, wholesale prices dropped another 15 to 20% through late 2025, and the average lab grown center stone purchased in 2026 is 2.5 carats, nearly double what it was in 2019.
For US jewelry designers, retailers, and studio jewelers, this creates an enormous opportunity. But buying loose lab grown diamonds wholesale is not the same as buying polished naturals through a traditional channel. The sourcing decisions you make, including growth method, grading lab, clarity tier, shape, and supplier type, have a direct and measurable impact on your margins, your customer satisfaction, and your ability to restock consistently.
At Gems Diamonds By Shikha (GDBS), we manufacture and export loose lab grown diamonds directly from Surat to wholesale buyers across the United States. This guide walks you through every step of the sourcing process so you can buy with confidence, whether you are building your first lab diamond collection or scaling an existing one.
Step 1: Understand What Loose Lab Grown Diamonds Actually Are
Before sourcing, you need to be clear on the terminology, because your retail customers will ask.
Lab grown diamonds are real diamonds. They share the same chemical composition, crystal structure, hardness, and optical properties as mined natural diamonds. With a rating of 10 on the Mohs hardness scale, lab grown diamonds are as hard as natural diamonds, making them highly resistant to scratching and ideal for long-lasting jewelry.
The only difference is origin. Natural diamonds formed in the Earth's mantle over billions of years. Lab grown diamonds are produced in controlled environments in weeks using one of two methods.
What "loose" means: A loose lab grown diamond is any lab grown diamond sold as an individual stone, not set into jewelry. Loose stones give designers and retailers full flexibility over setting choice, metal type, and design. Buying loose wholesale is how most professional jewelry businesses source their diamond inventory.
Step 2: Understand CVD vs. HPHT, the Two Growth Methods
Every wholesale lab grown diamond was grown using one of two processes. Understanding the difference helps you buy smarter and answer customer questions confidently.
CVD (Chemical Vapor Deposition)
CVD uses a layered, gas-based growth method done in a vacuum chamber, where carbon atoms are added one by one to build the diamond structure. Multiple diamond seed wafers are placed on a base, and the chamber is filled with a hydrocarbon gas mixture, such as methane and hydrogen. Microwave or other energy sources create a plasma that breaks down the gases, allowing free carbon to settle and form crystals on the seeds in controlled layers over several weeks.
CVD produces Type IIa diamonds, the purest diamond type, typically with better color consistency and fewer inclusions. Most high-quality colorless lab diamonds on the market today are CVD-grown. For engagement ring designs and large solitaires, CVD is generally preferred by wholesale buyers.
HPHT (High Pressure High Temperature)
HPHT uses mechanical pressure and catalysts to rapidly simulate Earth's mantle conditions, often yielding diamonds that grow in different directions and may contain metallic traces. The HPHT segment is projected to dominate the market with a share of 54.45% in 2026, as the method typically assists in developing better quality diamonds and closely resembles the production method of natural diamonds.
HPHT is effective for producing certain fancy colored diamonds, including fancy yellow and blue, and for smaller colorless stones. Lower quality CVD stones can sometimes show brownish tints or grain lines if the growth process was too fast, while HPHT stones can occasionally exhibit a faint blue nuancing caused by the presence of boron used to accelerate growth.
For wholesale buyers: CVD is generally the safer choice for large colorless solitaires. HPHT offers strong options for fancy colored lab grown diamonds. At GDBS, our lab grown diamond collection spans both methods, organized by shape and clarity for straightforward wholesale sourcing.
Step 3: Know the 4Cs for Lab Grown Diamonds
Lab grown diamonds are graded using the same 4Cs framework as natural diamonds: cut, color, clarity, and carat. Lab grown diamonds are evaluated based on the same criteria as natural diamonds, including the 4Cs, and a certified gemologist or reputable gemological laboratory will assess these factors to determine the overall quality of the lab grown diamond.
Here is how each factor plays out specifically for wholesale lab grown diamond buyers in the USA:
Cut
Cut is the most important quality factor for visual impact. A well-cut diamond reflects light optimally and produces maximum brilliance regardless of whether it is lab grown or natural. For round brilliants, look for Excellent or Very Good cut grades. For fancy shapes, evaluate the length-to-width ratio and visual symmetry. Never sacrifice cut to save cost, it is the difference between a stone that sells itself and one that sits in inventory.
Color
Prior to 2020, most CVD-grown diamonds were near-colorless, with color grades from G to N. The year 2020 saw a significant increase in submissions of colorless-grade diamonds (D, E, or F), likely due to improvements in growth and treatment procedures. Today, over 85% of lab grown diamonds on the wholesale market grade D to F in color, making high-quality colorless stones the norm rather than the exception.
For wholesale sourcing, D to F color is the standard for engagement-ring-quality stones. G to H is acceptable for fashion jewelry and multi-stone designs where color is less visible.
Clarity
VS1 and VS2 clarity is the sweet spot for most wholesale buyers. Inclusions are not visible to the naked eye, but the price is significantly lower than VVS grades. For engagement ring centerpieces where clients inspect the stone closely, VS1 or higher is a strong recommendation. For accent stones, pave, or lower price point designs, SI1 is often acceptable and delivers strong margin.
Note: Lab diamonds may show metallic inclusions from growth, especially in HPHT, or distinctive growth patterns. These differences are only visible under magnification with specialized equipment and do not affect the design or appearance of the finished piece.
Carat
Lab grown diamonds are available in a far wider carat range than was possible five years ago. Large lab grown diamonds, 3 carats and above, are now readily available at wholesale and represent an excellent opportunity for US retailers who want to offer statement pieces that were previously out of reach for most buyers. At GDBS, our lab grown diamond collection is organized by carat range from below 0.99ct through 7ct and above, making it easy to source specific size tiers for different collection price points.
Step 4: Choose the Right Shapes for Your Market
Shape is the most visible design decision in any diamond purchase. The US market in 2026 has clear shape preferences that wholesale buyers should understand before building inventory.
Round brilliant is still the most purchased diamond shape in the US overall and offers the most consistent demand and resale. Every collection should carry round brilliant lab grown diamonds.
Oval has overtaken princess cut as the second most popular shape in US engagement ring sales. Its elongated silhouette appears larger per carat and suits the maximalist sizing trend driven by lab grown affordability.
Cushion is a perennial strong seller for vintage-inspired and halo settings. Cushion cut lab grown diamonds at 2 to 3 carats are a particularly strong commercial proposition.
Pear is one of the fastest growing shapes in US bridal in 2026, driven by celebrity influence and its versatile east-west or north-south setting options.
Radiant, emerald, marquise, princess, and heart all serve specific buyer aesthetics. Building a collection with depth across at least four to five shapes gives your retail customers genuine choice and positions your store as a complete sourcing destination.
Browse the full GDBS lab grown diamond collection to see available shapes and carat ranges.
Step 5: Understand Lab Grown Diamond Certification
Every loose lab grown diamond intended for resale should come with a grading certificate from a recognized gemological laboratory. Certification verifies the 4C grades independently and confirms the stone's identity as lab grown.
IGI (International Gemological Institute) is the most widely used certification lab for lab grown diamonds globally. IGI pioneered the grading of lab grown diamonds in 2005 and continues to lead the field today, with lab grown diamond certification demonstrating unparalleled expertise in the testing and documentation of loose stones. IGI certificates are widely accepted by US retailers and resellers and are the standard for wholesale lab grown diamond transactions.
GIA (Gemological Institute of America) also certificates lab grown diamonds. Note that GIA updated its lab grown diamond grading system effective October 1, 2025, moving away from traditional 4Cs grading to a simplified approach that categorizes lab grown diamonds broadly as either "Premium" or "Standard." This change reflects that over 95% of lab grown diamonds fall into a narrow band of high color and clarity grades. For most wholesale buyers in the US, IGI certification remains the preferred standard for lab grown diamonds due to its specificity and market familiarity.
What to look for on any certificate:
- Stone identity confirmation as laboratory grown
- Full 4C grades (or IGI equivalent)
- Growth method disclosed (CVD or HPHT)
- Laser inscription number matching the certificate
- Grading laboratory name and report number for online verification
At GDBS, certification options are available for wholesale lab grown diamond orders. For specific certification requirements, contact Shikha directly through the wholesale enquiry page.
Step 6: Understand 2026 Wholesale Pricing
Lab grown diamond wholesale prices have fallen dramatically and continue to decline. Wholesale prices dropped another 15 to 20% through late 2025, with 1-carat G/VS1 stones now available under $1,000. This price trajectory has fundamental implications for wholesale buyers:
Buy to order rather than carry large inventory. Because prices continue to decline, holding large stocks of lab grown diamonds carries real depreciation risk. Build a sourcing relationship that allows fast, consistent reorder at current market rates.
Margins are in the carat-size premium. While per-carat wholesale costs are falling, retail buyers continue to respond strongly to larger stones. A 2.5-carat lab grown diamond priced appropriately for its carat weight creates strong perceived value at a retail price that still delivers healthy margin.
CVD tends to carry a slight premium over HPHT for large colorless solitaires at the wholesale level, as many international wholesale vendors prefer CVD for large solitaires because it is seen as the cleaner technology, with a slight liquidity advantage at 2 carats and above.
Price check before every order. The lab grown diamond wholesale market moves monthly. Before placing any significant wholesale order, verify current price benchmarks through your supplier relationship. At GDBS, wholesale pricing is available directly through Shikha and reflects current Surat market rates without middleman markup.
Step 7: Choose the Right Wholesale Lab Grown Diamond Supplier in USA
This is the most consequential decision in your sourcing process. The quality of your supplier determines everything that comes after it.
Here is what to look for and what to avoid:
Source as directly as possible. Every intermediary between the cutting unit and your purchase adds margin without adding value. A manufacturer who cuts in Surat and exports directly to the US is your strongest commercial option. All production being in-house allows suppliers to provide diamonds directly from production, guaranteeing the possibility of better pricing.
Verify gemological expertise. Your supplier should be able to advise on cut quality, clarity implications, CVD vs HPHT for specific use cases, and certification options. If a supplier can only quote prices and shapes without explaining the quality rationale, that is a red flag.
Confirm consistent reorder capacity. The most important question for wholesale sourcing is not the first order, it is whether the supplier can consistently supply similar quality on reorder. Spot-lot suppliers who cannot guarantee consistency create problems for production jewelers and retailers building repeatable collections.
Check for disclosure compliance. Lab grown diamonds must be disclosed as such. Any supplier who is vague about origin, growth method, or certification is a compliance risk for your business.
At GDBS, Shikha is a certified gemologist with 20 years of experience who handles wholesale enquiries directly. Our lab grown diamonds are produced through our own Surat manufacturing operation, certified by IGI, and available with full disclosure of growth method and specifications. We supply individual stones for sampling and larger wholesale lots for collection builds.
Step 8: Place Your First Wholesale Order the Right Way
Once you have chosen your supplier, here is how to structure your first wholesale order to minimize risk and maximize learning:
Start with a sampling order. Before committing to a large wholesale lot, order two to five stones across your target shape, carat, and clarity range. Inspect them against the certificates. Evaluate light performance under different lighting conditions. Compare to your retail price targets.
Specify clearly. For each stone in a wholesale order, specify: shape, carat weight range, color grade range, clarity grade, cut grade (for round brilliants), and certification lab preference. The more specific your brief, the more consistent your supply.
Photograph and document on receipt. When stones arrive, document them against certificates before any further processing or setting. This protects you in the rare event of a dispute.
Build a reorder relationship. After a successful first order, establish a reorder cadence with your supplier. Regular buyers at GDBS receive priority on newly available shapes and sizes, which matters when specific stones are in high demand.
Shop Wholesale Loose Lab Grown Diamonds at GDBS
Browse the full GDBS lab grown diamond collection, organized by shape (cushion, oval, pear, radiant, emerald, marquise, princess, round, heart) and carat weight. For wholesale pricing, bulk orders, certification requirements, or custom sourcing, contact Shikha directly here.
Frequently Asked Questions
Q: What is the minimum order for wholesale loose lab grown diamonds at GDBS?
A: GDBS supplies both individual stones for sampling and larger wholesale lots. There is no strict minimum for a first order. Contact Shikha directly through the wholesale enquiry page to discuss your specific requirements and volume.
Q: Should I stock CVD or HPHT lab grown diamonds for my US retail collection?
A: For large colorless solitaires intended for engagement rings, CVD is generally preferred by US wholesale buyers for its Type IIa purity and cleaner color profile. For fancy colored lab grown diamonds, HPHT offers strong options. Many wholesale buyers stock both. At GDBS, both methods are available, and Shikha can advise on the right choice for your specific collection.
Q: Do GDBS lab grown diamonds come with IGI certification?
A: Certification options are available. Contact Shikha through the wholesale enquiry page to confirm certification requirements for your specific order.
Q: How often do lab grown diamond wholesale prices change?
A: The lab grown diamond wholesale market has seen prices fall 15 to 20% annually in recent years and prices continue to shift monthly. GDBS wholesale pricing reflects current Surat market rates. For the most current pricing, contact Shikha directly rather than relying on prices from older catalog listings.
Q: What shapes of loose lab grown diamonds does GDBS carry?
A: The GDBS lab grown diamond collection covers cushion, oval, pear, radiant, emerald, marquise, princess, round, and heart shapes, organized by both shape and carat weight range. Browse the full collection here.
Q: Are lab grown diamonds a good choice for US engagement ring collections in 2026?
A: Yes. Lab grown diamonds now represent over 55% of engagement ring center stones sold in the USA, and the average center stone size purchased has grown to 2.5 carats due to the dramatic price advantage. For US designers and retailers building engagement ring collections, loose lab grown diamonds offer strong margins, consistent quality, and high buyer demand.