One chain manufacturer describes the process as follows:
"24 carat pure gold is alloyed with, copper, zinc, and silver to form carat gold
alloys of varying pureness-10Kt, 14Kt, and 18Kt. The alloy is heated to a molten state in
a graphite crucible. The alloy is drawn through a die from the base of the crucible.
Rollers, working in regular short pulses pull the metal. The metal is formed into a
tubular rod 1 inch in diameter.
A small rod, known as the solder core is cast separately and slid inside the tubular
rod. The core has a different recipe to the rod and has a lower melting point. This
enables the links in the chain to be soldered at a later stage.
The rod is then rolled and drawn down in increasingly smaller sizes. The smallest
diameter the wire can be formed into is roughly three times the size of a human hair. As
the wire is worked it hardens. Periodically the wire is woven on a spool, heated to a
temperature just below its melting point and then quenched in water. This releases the
hardness so the wire can be drawn again.
The wire is formed into a chain by a machine or assembled one link at a time by
hand."
I'm fascinated by these machines. They make links using a spiral die or by forming the
wire over a mandrel. To make the chain the wire feeds, each time, through the last formed
link. The wire is placed on a conveyor belt furnace and then heated to a temperature above
the melting point of the solder core but below the melting point of the outside rod. The
solder flows to close the link.
Some styles of chain are then cut to a mirror finish using a diamond finishing bit
rotating at speed in excess of 20,000 rpm. The chains are finished and polished.
In some cases chains are electroplated to brighten the color and cover the solder
joints. This is done to prevent the solder joints from discoloring.
This process will typically vary from manufacturer to manufacturer. The care in which
the chain is produced, the quality control of the product, and the steps taken to form the
wire into a chain all affect the finished product's value.
Are there seconds in chain just as there are in other products? Yes, as you can image
things can go wrong. When a manufacturer is dissatisfied with his product he has the
choice to either start over or sell the product as a second. You'll find much of this
chain is sold at a "So called discount".
