Diamond Suppliers in China
Mann Gems LLP supplies certified natural diamonds and lab grown diamonds to jewelry manufacturers and wholesalers across China. We work directly with production hubs in Shenzhen and Guangzhou, shipping loose diamonds in bulk from our base at Bharat Diamond Bourse, backed by GIA and IGI certification and 15+ years in the diamond trade.
Diamond Supplier in China: Natural & Lab Grown Diamonds for Wholesale Buyers
China’s jewelry manufacturing runs through two centers more than any others: Shenzhen’s Shuibei district, which alone handles a large share of the country’s diamond wholesale trade, and Guangzhou’s Panyu district, known nationally as the jewelry capital for fashion and semi-fine production. Both are manufacturing hubs, not raw material sources, which means factories there are constantly sourcing loose natural diamonds and lab grown diamonds from outside suppliers to feed production. That’s exactly where Mann Gems fits in, as a trusted Diamond Supplier in China.
Mann Gems is a leading Diamond Supplier in China, supplying certified loose stones directly to manufacturers running that kind of production, rather than selling finished jewelry ourselves. As a dependable natural diamonds supplier and lab grown diamond supplier, every stone leaves our facility with GIA certified or IGI certified documentation attached, which matters more in this market than most. Buyer guides covering China’s jewelry districts routinely flag inconsistent, unverifiable in-house certificates as one of the biggest risks facing manufacturers sourcing loose diamonds wholesale locally, and that’s a risk we help eliminate.
Diamond Quality Standards
Every diamond we supply, natural or lab grown, is checked against the 4Cs before certification:
- Cut: governs how light returns off the stone, the main driver of visible sparkle.
- Color: the scale from colorless to faint yellow; colorless commands the premium.
- Clarity: internal and surface characteristics; fewer inclusions means a rarer, more valuable stone.
- Carat: raw weight, with price accelerating disproportionately as size increases.
Finish and symmetry are reviewed on top of the 4Cs, so what a manufacturer receives matches exactly what was quoted, no surprises on unboxing.
PRODUCTS
get in touch
What We Supply: Natural Diamonds & Lab Grown Diamonds
We supply both natural diamonds and lab grown diamonds to jewelry manufacturers and wholesalers across China, each independently graded and certified before it ships. Here’s what’s available:
Natural Diamonds: Earth Mined Brilliance, Sourced at the Bourse
Every natural diamond we supply took billions of years to form and is graded on cut, color, clarity, and carat before it carries a certificate from a recognized lab. Chinese manufacturers producing bridal and heirloom-grade jewelry still lean toward natural stock for exactly this reason, the provenance is part of what their end customer is paying for.
Natural diamonds remain the preferred choice for China jewellery manufacturers producing bridal, investment, and heirloom-grade jewellery, where provenance and long-term value retention matter most to end customers.
Lab Grown Diamond Supplier for the China Market
Lab grown diamonds share the identical chemical and optical structure of natural stones, the difference is entirely in formation: HPHT or CVD technology in a controlled setting instead of geological pressure over billions of years. Demand for certified lab grown stock among Chinese manufacturers has grown quickly, largely because it lets factories offer a lower price point without sacrificing grading transparency. It’s worth noting we supply diamonds specifically, lab grown or natural, not moissanite or other simulants, which are a separate and much larger category in this market. We supply:
Demand for certified, competitively priced lab grown diamonds is growing among Iranian jewellery manufacturers looking to offer affordable, certified stock without compromising on grading transparency. We supply:
Best Loose Diamond Supplier to China
We supply diamonds as What we ship is unset, ungraded-into-jewelry stone, pure loose diamonds inventory ready for production. Manufacturers in Shenzhen and Guangzhou set, brand, and sell it under their own name, that production step stays entirely theirs. We supply the raw certified loose diamond input their line runs on.
Diamond Shapes Available
We cut and select parcels across all eleven commercially traded shapes, matched to what China’s jewelry manufacturers actually order for bridal, fashion, and export-focused production.
ROUND
PRINCESS
CUSHION
OVAL
EMERALD
HEART
PEAR
MARQUISE
ASSCHER
RADIANT
ROSE
Certified Diamond Supply & Wholesale Services in China
Diamond sizes, certified supply, custom sourcing, wholesale terms, and secure shipping for jewelry manufacturers across China.
Stock spans melee sizes for pave and accent settings through solitaire grade centre stones. Carat availability is confirmed against live inventory at the time of enquiry, since market pricing shifts daily.
Every certified stone carries a grading report and an independently verifiable report number, something that matters more in a market where in-house, unverifiable certificates are common. We supply diamonds certified by GIA (Gemological Institute of America) and IGI (International Gemological Institute), across both natural and lab grown categories.
- GIA (Gemological Institute of America): the industry benchmark for grading strictness and consistency.
- IGI (International Gemological Institute): a leading lab for both natural and lab grown certification.
Manufacturers in China with a specific production run can request:
- Custom carat and size ranges matched to a manufacturing schedule
- A specific shape mix, round only, fancy only, or blended
- Certification tier by lab, GIA or IGI, to match your market positioning
- Natural, lab grown, or a combined natural and lab grown parcel
Every custom request is checked against current stock and certification availability before we confirm it.
We supply jewelry manufacturers and wholesalers across China’s key production regions, from Shenzhen’s Shuibei district to Guangzhou’s Panyu manufacturing zone.
Cities We Serve
- Diamond Supplier in Shenzhen
- Diamond Supplier in Guangzhou
- Diamond Supplier in Shanghai
- Diamond Supplier in Beijing
- Diamond Supplier in Dongguan
Bulk is the model. We work in carat ranges, shape mixes, and certification tiers rather than one-off sales, and order size is set by production need rather than a fixed minimum. Manufacturers new to us often start with a trial parcel before moving to a running order tied to a production schedule.
Every shipment is packaged to protect stones in transit and shipped internationally with insurance coverage, with certification documentation traveling alongside so it can be checked against each stone on arrival. A meaningful share of India-origin diamond trade into Greater China routes through Hong Kong’s logistics network before reaching mainland
All general-trade diamond imports into mainland China are legally required to pass through the Shanghai Diamond Exchange (SDE), the country’s sole authorized channel, set up under China’s State Council. As of November 1, 2025, the VAT exemption that previously applied to SDE-channeled diamonds was removed, so both rough and polished diamonds sold into the domestic market now carry the standard 13% import VAT. If you’re importing for domestic sale in China, we’d recommend confirming current SDE and customs procedures with your import broker, since this is an area that’s changed recently and may continue to evolve.
Why Choose Mann Gems
Jewellery manufacturers and wholesalers choose Mann Gems LLP because we combine over a decade of industry expertise with certified diamond quality and a straightforward buying process.
- 15+ years of experience in the natural and lab grown diamond trade, established in 2005.
- GIA and IGI certified diamonds on every stone, independently graded before it ships.
- Trusted by 1,000+ clients globally, built on repeat orders rather than one-off sales.
- Ethically sourced diamonds aligned with Kimberley Process standards.
- Both natural and lab grown supply from one relationship, so manufacturers aren't managing two separate vendors for two categories.
Send Your Diamond
Requirements
Our sourcing team responds within 4 business hours with a curated certified stone list and pricing. All inquiries are strictly confidential.
Natural Diamonds vs Lab Grown Diamonds Quick Comparison
| Factor | Natural Diamonds | Lab Grown Diamonds |
|---|---|---|
| Origin | Formed naturally in the earth’s mantle over billions of years | Created in a controlled lab using HPHT or CVD technology |
| Composition | Pure carbon crystal structure | Identical carbon crystal structure |
| Certification | GIA, IGI | GIA, IGI, GCAL |
| Typical Price Point | Higher, driven by rarity | Generally more accessible per carat |
| Resale Value | Higher and more stable long-term | Lower and more variable |
| Common UAE Buyer | Bridal, heirloom, investment-focused retailers | Fashion, volume, value-focused retail chains |
Find Your Perfect Diamond Parcel
Talk to our Mumbai desk today. We get back to you within one business hour.
Frequently Asked Questions: Wholesale Diamond Suppliers in China
Mann Gems supplies GIA and IGI certified natural and lab grown loose diamonds direct from India, giving Shenzhen and Guangzhou manufacturers a verifiable alternative to unstandardized local certificates.
We currently supply diamonds certified by GIA and IGI. If you plan to resell in mainland China’s domestic retail market, you may need to arrange NGTC certification or inspection separately through a local lab, since NGTC is China’s own domestic grading authority.
No. We supply lab grown diamonds, which share the same carbon structure and optical properties as natural diamonds. Moissanite is a different mineral (silicon carbide) with different optical and physical properties, and we don’t supply it.
General-trade diamond imports are required to pass through the Shanghai Diamond Exchange, China’s sole authorized channel. As of November 2025, imported diamonds sold domestically carry a 13% import VAT. We recommend confirming current procedures with your import broker for your specific order.
There’s no fixed minimum. We supply single solitaires for custom orders and larger parcels for manufacturers running production.
Yes, in round, fancy shape, rose cut, mix cut, and solitaire inventory, across both natural and CVD or HPHT lab grown categories.
You share carat, shape, and certification requirements, we match it against current stock, confirm grading and live market pricing, and ship internationally with insurance once the order is confirmed.
Yes. We send HD video, 360 degree views, and certificate scans over WhatsApp or email, and can set up a live video call if you’d like one.