Not every join in a piece of jewellery needs a flame. Cold connections are mechanical joins — rivets, eyelets, tabs and stitches — that hold parts together with nothing but carefully fitted metal. They are among the oldest solutions in the jeweller's workshop, and they remain the right answer whenever heat would do more harm than good.
When a jeweller chooses not to solder
The obvious case is heat-sensitive material. Wood, shell, horn, acrylic, pearls and most gemstones cannot survive soldering temperatures, so any design that combines them with metal must be joined cold. Enamelled surfaces are another no-fire zone: a second trip through the torch would destroy glass that has already been fused.
Cold connections also solve problems that soldering creates rather than solves. Some combinations of dissimilar metals resist solder or corrode at the seam. And a row of neat rivets can be a design feature in its own right — a visible, deliberate line of stitches in metal that gives the piece structure and ornament at once. Deciding when to use a cold connection instead of a solder seam is itself a design skill, and it is one of the projects in the intermediate Traditional Metalsmithing 2 course at JDMIS, where learners build a complete cold-connection piece from planning to flush-set gemstone.
Preparation: parts, design transfer and texture
A cold connection only works if the parts are prepared properly. Each layer is fabricated, filed clean and fitted so the surfaces meet flat — gaps that a solder seam could fill become wobble and misalignment in a riveted piece. The design is then transferred to the metal so that hole positions land exactly where planned on every layer, which is the difference between a rivet that pulls a piece together and one that fights it.
This is also the natural moment to add texture. Roll printing — running a patterned or shaped object through the rolling mill with the metal — presses a permanent relief into the surface before any holes are drilled. It is an optional step in the cold-connection project, and one of the fastest ways to turn a flat blank into something that reads as designed rather than cut out.
Rivets and eyelets
The workhorse of the family is the rivet: a short length of wire passed through matching holes in the layers, then flattened on both ends so the heads clamp the stack together. Done well, the process is unforgiving in a satisfying way. The wire must fill its hole snugly — a loose rivet is a failed rivet — and is trimmed to stand only slightly proud of each surface. The piece rests on a steel block so the hammering has something to push against, and the blows fall evenly from both sides, so the two heads grow at the same rate and the stack stays under equal pressure. Because the heads are formed by hammering, the maker controls how big, how flat and how decorative they become. Eyelets are the hollow cousins — short tubes flared outward at each end with a setting punch — and they read as tidy rings on the surface while doing the same clamping job, with the added option of passing a cord, a jump ring or a second layer through the opening.
Planning the location of each connection is the real craft. Rivets placed on a visual axis look intentional; rivets scattered wherever the drill happened to land look like repairs. In the workshop the sequence is deliberate: clean up the parts, decide the connection points as part of the design, then rivet — first in demonstration, then on your own piece.
Invisible rivets
Sometimes the join should disappear. An invisible rivet is set below the surface of the metal: the hole is countersunk, the rivet is formed, and the seat is filled and finished flush so that nothing shows but clean metal. The piece holds together exactly as if it had been soldered, but no heat ever touched it — which is what makes the technique invaluable when the design includes material that must never see a flame.
Finishing — and a stone, cold-set
Final finishing brings the layers to one even surface, blends the rivet heads and removes every mark that the process picked up along the way. And because the piece was joined cold, it can stay cold to the very end: the project finishes with a flush-set gemstone, a stone secured in a burnished seat in the metal with no heat and no prongs — a small, satisfying proof of how complete a no-torch piece can be.
Cold connections sit inside a bigger picture of how jewellery is made: some pieces are cast, some are built from sheet and wire with solder, and some — the ones that mix materials or show their structure proudly — are joined by pure mechanics. If that distinction interests you beyond reading, the foundation metalsmithing course covers the bench basics, and cold connections are taught as a full project in Traditional Metalsmithing 2.