A startup brand sent a factory a hand-drawn sketch of a signet ring and asked for 500 pieces. The quote came back two weeks later, but the first sample was the wrong width, the wrong depth, and the wrong finish. The buyer had assumed "OEM" meant the factory would read their mind. It does not. OEM jewelry factory service is a handoff process: the more precisely you hand off at each stage, the fewer rounds of revision you pay for. This article walks through the chain from first sketch to shipped carton and lists what you owe the factory at every step.
Stage 1: Design intake and CAD
The factory cannot cast a sketch directly. The first real artifact is a CAD model. You provide reference images, dimensions (ring size, band width, stone diameter), material, and any finish notes (brushed, high-polish, matte). The CAD artist returns renders from three angles within 3-5 days. This is the cheapest stage to change anything — a 30-minute CAD tweak costs nothing, while a re-cast after wax costs days.
Stage 2: 3D printing and wax approval
Once the CAD is approved, a resin or wax pattern is printed. This physical pattern is what you actually touch before metal is poured. Measure it, try it on a sizer, check the weight and proportions. Approval here is the point of no return for geometry. After this, changes mean re-printing and re-casting.
Stage 3: Casting and cleanup
The approved pattern is mounted on a tree, invested in plaster, burned out, and centrifugally cast in your chosen alloy — 925 sterling silver, 10k/14k gold, or rose gold. After casting, each piece is cut from the tree, tumbled, and hand-filed to remove sprues. Porosity is checked under magnification; a porous piece is scrapped here, not after setting.
Stage 4: Setting, finishing, plating
Stones are set by hand — prong, bezel, or pavé depending on the design. Finishing then removes tool marks and builds the final surface. For white silver and white gold, rhodium plating sits on top; we plate to 0.5µm where the industry default is 0.3µm, which keeps the white finish from showing yellow over months of wear.
Stage 5: QC, packing, export
Every finished piece is weighed, sized, louped, and pull-tested. Acceptable lots are packed in poly bags, sorted by size, and loaded into export cartons. Export documents — commercial invoice, packing list, and certificate of origin — travel with the shipment so DDP customs clearance is smooth for US and EU importers.
What you owe the factory at each handoff
| Stage | What you provide | What the factory returns |
|---|---|---|
| Design intake | Sketch, dimensions, material, finish notes | CAD render in 3-5 days |
| Pattern approval | Written approval of the printed pattern | Casting scheduled |
| Pre-production sample | Approval of first metal sample | Bulk run green-lit |
| Final lot | Shipping address and consignee details | Cartons, docs, tracking |
The buyers who sail through OEM are the ones who write "approved, proceed" rather than "looks fine, go ahead." Vague approvals create arguments later. Exact approvals eliminate them.
Frequently Asked Questions
What is the difference between OEM and private label jewelry?
OEM means the factory manufactures to your design specification; the design and tooling are yours. Private label means you sell existing factory designs under your brand name. OEM suits brands with original designs; private label suits buyers who want speed and proven styles.
How many CAD revision rounds are typical?
Two to three revision rounds are normal before the pattern is printed. More than that usually means the original brief was short on dimensions. Give exact measurements up front to keep revisions to one round.
Can the factory supply the stones, or do I?
Most factories source stones themselves, including moissanite (Mohs 9.25, GRA-certified) and small melee. You can also supply your own stones if you have a trusted supplier; the factory will set them on a stones-on-consignment basis.
How long does the full OEM process take?
A typical OEM run takes 5-8 weeks from CAD kickoff to carton: 3-5 days CAD, 2-3 days printing, 5-7 days casting, 7-10 days setting and finishing, 2-3 days QC, plus shipping.
Who owns the CAD files and tooling?
Negotiate this in writing at the start. Standard practice is that once tooling fees are paid in full, the designs and patterns belong to you and the factory will not reuse them for other buyers.
Takeaways
- The cheapest place to fix a design is in CAD — give exact dimensions up front.
- Approve the physical wax or resin pattern before metal is cast.
- Insist on a written pre-production sample approval before the bulk run.
- Negotiate ownership of CAD files and tooling in the initial agreement.
Have a design ready to turn into production? Send us your sketches or CAD files — we return a CAD render in 3-5 days and a firm lead time. See our OEM design service, walk the floor in the factory tour, or read our buying guides.
Rhodium plating, which gives white gold jewellery its bright finish, is covered in the Wikipedia article on rhodium.
