Jewelry That Never Comes Off
What Everyone's Wearing
Our most-loved pieces — crafted in 316L stainless steel, built to be worn every day.
Engineering Meets Artistry
We don't just make jewelry. We manufacture it with Swiss-level precision — 5-axis CNC machining, mirror polishing by hand, and molecular PVD bonding. Every piece is inspected 3 times before it leaves our studio.
316L Surgical-Grade Steel
Nickel-free, hypoallergenic, and waterproof. Safe for sensitive skin — shower, swim, sweat, repeat.
CNC Precision ±0.05mm
Every piece is 5-axis CNC machined — the same tolerance as Swiss watchmaking. No casting flaws.
Hand Mirror Polish
Artisans with decades of experience hand-finish each piece. Our mirror polish catches light at every angle.
EU REACH Certified
Meets the strictest international safety standards. Third-party lab tested. No harmful substances — guaranteed.
Find Your Style
From bold chains to subtle studs — explore our full range of 48+ designs across 5 collections.
Made in Our Dongguan Workshop.
5-axis CNC machining, hand mirror polishing and three-stage QC behind every piece.
Sustainably Made
316L steel is 100% recyclable. Our PVD process uses zero water and zero toxic chemicals. We offset carbon in our manufacturing. Every piece is built to last decades — not seasons.
Read Our Impact Report →The Steel Journal
• How to Layer Chains Like a Stylist
• PVD vs Electroplating: The Truth
• Why 316L Steel Is the Future of Jewelry
Visit Blog →LUMYU Rewards
Earn 1 point per $1 spent. Redeem for discounts and exclusive early access. VIP members get free engraving for life.
Find Your Perfect Fit
Every body is unique. Find your exact size in 60 seconds — rings, chains, and bracelets.
Ring Size Chart
| US Size | Inner Diameter (mm) | Circumference (mm) | UK / EU |
|---|---|---|---|
| 5 | 15.7 | 49.3 | J½ / 49 |
| 6 | 16.5 | 51.8 | L½ / 52 |
| 7 | 17.3 | 54.4 | N½ / 54 |
| 8 | 18.1 | 56.9 | P½ / 57 |
| 9 | 18.9 | 59.5 | R½ / 60 |
| 10 | 19.8 | 62.1 | T½ / 62 |
| 11 | 20.6 | 64.7 | W½ / 65 |
| 12 | 21.4 | 67.2 | Y / 67 |
Most common: Women 6-7, Men 9-10. Thicker bands? Size up +1.
Necklace Length Guide
📞 How to Measure at Home
- Wrap a string or strip of paper around the base of your finger.
- Mark the point where the ends overlap with a pen.
- Measure the string against a ruler (in millimeters).
- Find your measurement on the circumference column above.
- Pro tip: Measure at the end of the day when fingers are largest. If between sizes, go up.
🖨 Printable Ring Sizer
Print this guide at 100% scale (do not "fit to page"). Wrap around your finger to read your size directly.
Print at 100% · Wrap around finger · Read size at overlap point
Forged in Precision.
Worn with Purpose.
LUMYU was born in Dongguan's precision manufacturing district, where third-generation metalworkers have been crafting world-class products for over 15 years. What started as a B2B supply operation for Europe's top jewelry brands became something more — a direct-to-you label that cuts out the middleman and delivers Swiss-level craftsmanship at a fraction of traditional luxury prices.
Every LUMYU piece is 5-axis CNC machined to ±0.05mm tolerance — the same standard as Swiss watchmaking. Our artisans hand-polish each surface to a mirror finish. Our PVD coating bonds at the molecular level. The result: jewelry that survives the gym, the ocean, and everything in between — without losing its shine.
Years Experience
Countries
Happy Customers
Give the Gift of Forever Jewelry
Premium gift packaging, hand-written cards, and custom gift sets for bulk orders — make every occasion unforgettable.
Gift Box Upgrade
Premium matte black magnetic box + velvet insert + signed authenticity card. Ready to gift, no wrapping needed.
+ $4.90Handwritten Card
Your personal message, handwritten by our team on premium cardstock. Up to 200 characters.
FREE with any orderCustom Gift Packaging
Logo-embossed gift boxes, custom inserts and private-label gift sets — quoted per order for bulk and corporate gifting.
Available on Request3D/AR Virtual Try-On
See how every piece looks on you — before you buy. Point your camera, and our AR engine places the jewelry on your hand, neck, or wrist in real time.
Beta Launch Q1 2027 · Join the waitlist
Frequently Asked Questions
Will 316L stainless steel tarnish or turn my skin green? ▼
No — that's the beauty of 316L surgical-grade steel. It is nickel-free, hypoallergenic, and will never tarnish, rust, or turn your skin green. You can shower, swim, sweat, and sleep in it. The mirror polish and PVD coating create a protective barrier that keeps the steel bright and the finish looking new far longer than ordinary plating.
How does custom engraving work? ▼
Simply select "Add Engraving" on any product page. You can engrave up to 15 characters on chains and bracelets, or 8 characters on rings. We use precision laser engraving (±0.02mm accuracy) that etches directly into the steel — it will never wear off. Enter your text, preview it, and we'll produce it within 48 hours. Engraving adds $9.90 to your order.
What size chain / ring / bracelet should I order? ▼
Every product page includes a detailed size guide with measurements in both inches and centimeters. Chains come in 18" (choker), 20" (standard), 22" (mid-chest), and 24" (long). Rings follow US sizing (5-12) with a printable ring sizer. Bracelets come in 7" (standard) and 8" (large). Need a custom size? Select "Custom Sizing" — free of charge on all orders.
Do you ship to my country? ▼
Yes — we ship worldwide. Our primary B2B markets include US, Canada, UK, all EU countries, Australia, New Zealand, Japan, South Korea, Singapore, UAE, and more. Bulk freight terms (FOB / CIF / DDP) and lead times are quoted per order based on quantity and destination. Request a freight quote →
What's the difference between PVD gold plating and regular gold plating? ▼
Regular electroplating deposits a thin gold layer on the surface that wears off within months. PVD (Physical Vapor Deposition) bonds gold particles at the molecular level into the steel itself — creating a finish that is 8-10x more durable, completely waterproof, and will not fade, chip, or peel. Our PVD gold jewelry is shower-safe, pool-safe, and gym-proof.