Tension Setting
Also called tension set ring, floating setting
A tension setting is a stone setting that holds a gemstone by the spring pressure of the metal band pressing on it from two sides. Small grooves cut into the band grip the stone edge, and because there are no prongs or rim, the stone appears to float in a gap.
In other words, the band is sprung open and squeezes the stone between its two ends, so nothing covers the front of the gem.
How it holds
The metal has to be work-hardened so it keeps its spring, and the band is machined slightly narrower than the stone so it grips when the stone is forced in. Small seats or grooves in the ends stop the stone sliding. It is precise bench work and it cannot be resized like a normal band.
Because so little metal touches the stone, light enters from almost every direction. A well-cut stone in a tension setting is about as bright as jewelry gets.
Rendering a floating stone
The whole point of the setting is the empty space around the stone, and empty space is exactly what a weak render fails at. Without careful light bouncing through the gap, the stone loses its grip on the eye and looks pasted in.
The contact points do the convincing. Those two small areas where metal meets gem need a visible shadow and a slight compression of the highlight, or the ring reads as a stone hovering in mid air. We check that pair of contacts at full resolution on every tension-set piece.
Questions about Tension Setting
Is a tension setting safe?
Yes when it is made properly, since the spring pressure is considerable. It cannot be resized easily though, so sizing has to be right at the start.
Can you render a tension setting convincingly?
Yes. The work is in the contact points and the light passing through the open gap, and both get checked at full resolution before delivery.