Cadena Cubana de Miami

The geometry. A Miami closes its links more tightly, so each oval overlaps its neighbour through most of its length, uses thicker wire for the ring size, raises the top of the chain to a pronounced dome, and grinds the underside flat.

The result is a chain that is deeper front to back, heavier for its length, and stiffer along its run than a plain Cuban of the same width. It reads as one polished ridge rather than two rails with a seam between.

It is treated as its own style rather than a filter because those changes alter how the chain lies, how it reflects and how it is fastened, not merely how it looks in a photograph.

The dome is worked into the top of the chain after assembly, and it does two things. It gives each link a crest along the centre line, and because the links overlap so far, those crests join into one continuous ridge.

That ridge is what the chain reflects from. A single band of light runs the length of the chain and slides across the dome as it turns, which is the look the profile is chosen for.

The dome also adds depth. A Miami stands higher off the chest than a flatter chain of the same width, so it is seen from the side as well as the front and catches light from a wider range of angles.

So that the chain sits still. A link that is domed on top and rounded underneath would rock from side to side on the skin; grinding the back to a single plane gives the chain a base to rest on, like a tile.

The flat back is made on a lap after the dome has been formed, and it runs the full length of the chain, including the clasp housing, so every part of the run lies at the same height against the body.

It is also the reason the chain does not roll. With a rounded top and a flat bottom there is only one way for it to lie, and its weight keeps it there.

Because the seams are buried. The links overlap so far that the joints between them do not show on the top surface, and the crest of each dome runs straight into the crest of the next without a break.

Light falling across the chain therefore returns from a continuous ridge, and the eye follows it as a single bright line the full length of the piece. An ordinary Cuban shows its joints, and its light alternates along the run.

As the chain turns, the band moves across the dome from one side to the other, so the whole chain brightens and dims together rather than sparkling link by link.

No. Each link overlaps its neighbour through most of its length, so it has only a short arc of free movement before it bears on the next. The chain holds a firm smooth curve rather than draping loosely.

Around the neck that firmness is an advantage: the chain keeps its arc across the chest and does not bunch or sag. It also means the chain should be lifted on and off rather than folded.

Bent sharply across its depth, the overlapping links have nowhere to go and the chain can be strained at a joint. Stored flat or hung, it keeps its shape indefinitely.

Because it is built to the link. The box housing is made with the same dome on top, the same flat underside and the same width as the links, so that when closed it reads as one more segment of the chain rather than a fitting.

A fastening of that size carries the load of a heavy chain across its full width, where a small clasp would concentrate it on a single ring and become the point that gives first.

On heavier widths the housing carries a hinged latch on each flank that snaps over the joint. Both have to be lifted before the sprung tongue can be released, so the chain cannot open under a knock.

It can carry one at the narrower widths, but it is usually worn without. The chain is chosen for the band of light along its crest, and a pendant sits across that band and interrupts it.

The dome also gives a bail a rounded surface to rest on rather than a flat one, so a pendant tends to sit slightly forward of the chain rather than lying against it.

Where a pendant is wanted, a wide bail cut to clear the full depth of the link is needed, and the pendant should be heavy enough not to be moved about by the chain's own stiffness.

Alone, and visible. Its depth and weight make it the piece rather than a carrier, and it is most often worn outside the collar or on bare skin so that the full run of the dome is seen.

It settles into a firm arc across the chest and stays there. Because the flat back keeps it still, it can be worn all day without adjusting, and the clasp remains at the nape.

Layered, the Miami is always the outer and lower chain. A finer chain sits above it, since nothing lighter can hang in front of its depth without being pushed out of line.

Yes. The flat underside rests on the chest as a plate, the weight holds it down, and the links have too little free movement for the chain to ripple or swing. It moves with the body as one piece.

There is no rolling, because a chain with a domed top and a flat bottom has only one way to lie, and no creeping of the clasp round the neck, because the run is equally weighted on both sides.

A very active day may shift the arc a little to one side, and it is pulled back to centre by hand. That is the extent of the adjustment a Miami needs.

From around six millimetres, where the dome is present but subtle and the chain reads as a firm, deep Cuban, through eight, ten and twelve millimetres, which is the range in which the profile is unmistakable.

Fourteen, sixteen and eighteen millimetres are made for those who want the chain as the whole statement, and wider still exists. At these sizes the box clasp carries latches on both flanks.

The shape of the link does not change as it grows; what increases is the depth of the dome and the mass of each link. Each listing states the width and karat of that chain.