Frequently Asked Questions
Everything you need to know about MadisonDia lab grown diamonds — from quality and certification to ordering, shipping, and returns. Can't find your answer? Contact our team anytime.
Who is MadisonDia?
MadisonDia is a Hong Kong-based lab grown diamond brand operated by Madison Avenue, a luxury retail company established in 2012. We began as an authorised boutique dealer for internationally renowned brands including Versace, Hugo Boss, and Moschino — and in 2023, we officially launched MadisonDia, applying over a decade of luxury expertise to lab grown diamonds.
You can verify our track record through our 5.0 rating on BUYMA with 1,300+ verified reviews.
Why are MadisonDia diamonds more affordable than traditional retailers?
We work directly with leading laboratories and manufacturers, eliminating all unnecessary intermediaries. This factory-direct model allows us to offer top-specification, IGI-certified lab grown diamonds at prices that consistently undercut traditional retailers — without lowering our standards.
Do you have a physical store I can visit?
Yes. Our private showroom is located at G11 Hankow Centre, 5–15 Hankow Road, Tsim Sha Tsui, Hong Kong. Our showroom holds certification under the Hong Kong Government's official
Are lab grown diamonds real diamonds?
Yes. Lab grown diamonds are chemically, physically, and optically identical to mined diamonds. They are created using advanced technology that replicates the natural diamond formation process — the same brilliance, hardness, and durability, without the environmental and ethical concerns of traditional mining.
What diamond grades does MadisonDia offer?
We exclusively offer top-tier diamonds — no inconsistent quality tiers, no upselling.
Every stone is independently certified by IGI and further evaluated using our proprietary MISI™ Sparkle Index — only diamonds scoring 80 or above are stocked.
Are your diamonds certified?
Yes. Every MadisonDia diamond comes with an IGI (International Gemological Institute) certificate, independently verifying its color, clarity, cut, and carat weight. You can verify your certificate directly on the IGI portal using the number provided with your order.
What is MISI™ — the MadisonDia Ideal Sparkle Index?
MISI™ is MadisonDia's proprietary diamond evaluation system, developed with IGI professionals, mathematicians, and software engineers. It goes beyond the traditional 4Cs to evaluate a diamond's real-world light performance — brilliance, fire, and scintillation — converting complex data into a clear score out of 100. We only stock diamonds scoring 80 or above.
Where can I learn more about choosing a lab grown diamond?
How does the diamond selection process work?
Once you place an order, we email you the IGI certificate of your selected diamond for review — before anything is shipped. If the specifications don't meet your expectations, our team will present at least 5 alternative diamonds of equivalent grade. If you're still not satisfied, you can request a full refund with no fees.
Do you offer custom jewelry?
Yes. MadisonDia offers fully custom rings, pendants, and earrings. The process includes CAD design approval and diamond selection before production begins, and you'll receive photos of the completed piece before shipment. Custom pieces are handcrafted within 5–15 business days.
Do you have coupon codes or discounts?
- Former Madison Avenue 14F customers can request a dedicated coupon via customer service.
- KOL / influencer-affiliated codes — please contact the influencer directly for their personal code.
What payment methods do you accept?
We accept all major payment methods:
Is shopping on your website secure?
Yes. Our website is fully protected with SSL encryption and all payments are processed via trusted gateways including Stripe and PayPal. We never store your payment details.
Do you ship internationally?
Yes. We ship worldwide from Hong Kong via fully insured couriers including DHL, FedEx, EMS, and SF Express. Every shipment includes your IGI certificate and all relevant documentation. Current destinations include Hong Kong, Japan, Taiwan, Singapore, Thailand, Australia, the USA, Canada, and more.
How long does delivery take?
- Loose diamonds: 0–2 business days processing + 2–8 business days shipping
- Custom jewelry: 5–15 business days production + 2–8 business days shipping
Customs processing times may add extra days for some destinations and are outside our control.
What is your return policy?
- Loose diamonds: Full refund within 30 days of delivery — unconditional.
- Finished jewelry: Refund as store credit within 14 days. A polishing fee of US$25–40 applies. Items must be returned in original condition with all certificates.
Which countries have free returns?
Free return shipping is available for customers in: Japan, Hong Kong, Macau, Taiwan, United Kingdom, United States, Canada, and Australia.
If your country is not listed, return shipping costs may apply. Please contact our team before sending any item back.
How long does a refund take?
Once we receive your returned item, it is inspected within 1–3 business days. Refunds are then processed and typically appear within 3–10 business days depending on your payment method and bank. You'll be notified by email as soon as your refund has been issued.
Still have a question? Our team is happy to help. Get in touch with us and we'll respond as soon as possible.