Our History
Founded in Hong Kong, 1992.
Osia began as a Hong Kong-based fine jewellery manufacturer and diamond trader, with production based across Hong Kong and mainland China. Over three decades, that manufacturing base grew into full in-house production: design, casting, and hand-setting done under one roof, rather than finished goods bought in from third parties.
Our clientele has always spanned both ends of the trade, from large chain retailers to independent designer boutiques - the same range of trade accounts we serve today, all on the same casting standards and quality control.
What We Do
Two trades, one relationship.
Our clients typically work with us across both sides of the business, sourcing loose diamonds for their own settings, and ordering finished jewellery built to specification. One account, one point of contact, both catalogues.
Fine Jewellery Manufacturing
Rings, earrings, pendants, bracelets, and necklaces, designed by us and produced through our manufacturing partners.
Natural Diamond Sourcing
Independently certified natural stones, sourced across every shape, carat, colour and clarity.
Lab-Grown Diamonds
Certified lab-grown stones, graded on the identical 4Cs scale as natural, a growing share of trade demand we source directly for.
Responsible Sourcing
Certification isn't a badge, it's a sourcing discipline.
Every natural diamond we handle is sourced consistent with the Kimberley Process conflict-free requirements. Lab-grown diamonds carry no such conflict-sourcing risk to begin with - they're grown, not mined - and are independently certified all the same (GIA, IGI, or GCAL). Precious metals come from refiners that meet responsible sourcing standards, not whichever supplier is cheapest that quarter.
That's why we keep full production traceability on every piece: we can answer where it actually came from, not just where it shipped from.
Private Label
Your brand, our production, protected by NDA.
We currently design and produce exclusive brand lines for 30+ companies under signed NDAs, from first design through ongoing stock replenishment. Each client's specifications, styles, gemstone and diamond quality grades, stamping, and account details are kept confidential and never shared with any other client or third party.
Global Presence
Three offices, one supply chain.
Supplying wholesale trade clients across Malaysia, Singapore, Indonesia, Japan, Australia, New Zealand, the United States, and a growing list of emerging and developed markets worldwide.
Osia International
Head Office · Hong Kong Unit 9D, 8 Hart Avenue Plaza, Tsim Sha Tsui, Kowloon hongkong@osiaintl.comOsia International (Pacific)
Australia Suite 109, 250 Pitt Street, Sydney, NSW 2000 aus@osiaintl.comFrequently Asked
About Osia, in short.
Is Osia a manufacturer or a supplier?
Manufacturer first. Osia is an ODM (Original Design Manufacturer) - we design and manage production through two dedicated manufacturing partners, rather than reselling finished goods bought from someone else.
How long has Osia been operating?
Since 1992, over three decades based in Hong Kong, growing from a jewellery manufacturer and diamond trader into a full ODM operation with offices across three countries.
Can Osia manufacture private-label or custom branded lines?
Yes - we currently produce exclusive brand lines for 30+ companies under signed NDAs, each with their own specifications, styles, and quality grades kept strictly confidential.
Ready to see trade pricing?
Applications are reviewed by our team. Most accounts are approved within a few business days.
Apply for Trade Access