Some of ORRO's contemporary engagement ring designs  take your breathe away. Literally. There are no prongs to hold on to the gems. Therefore you get to see the entire gem which you don't do with regular rings. With very refractive gems like diamonds, that translates to extra sparkles.

The whole ring acts like a tight spring to keep the gemstone in place. There are also tiny grooves in the metal which act as shelves. Tension rings have to be strongly constructed with special treatment and hardening processes. They also use 2-3 times the metal required for ordinary rings.

Generally speaking, tension set rings are made to order as resizing requires melting down the ring to make a new one. Another reason for the special order is each ring has to be designed to fit a particular stone's dimensions. Not just any stone, but the hardest ones like diamonds, rubies and sapphires which can take the enormous pressures exerted on them. Strong metals are used too like titanium and stainless steel. Gold can be used but it has to be alloyed with other metals.


Friedrich Becker of the German company Niessing was the first to come out with tension rings back in 1981. Since then other tension ring designers have improved on the alloying processes so tension rings today are lighter but still retain their strength.

What are they like compared to prong rings? Well, you can't snag a tension ring on your clothes etc nor are there prongs to weaken and break with time. You'd have to hit one very hard to make it lose its spring action. Opinions are divided but some jewelers consider tension set rings better than prong set ones.

References
Diamondinfo.org
Wikipedia : Tension ring

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Original Post by THE BEADING GEM
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