Tension set jewelry is among the most unique in appearance; however, many people are unsure whether a tension setting is strong enough to hold over time. This concern is actually invalid because a tension setting applies so much pressure on the gem that only certain types of stones can withstand the pressure. The four types of compatible gems are diamonds, rubies, moissanite and sapphires. Jewelers must take care that pressure is evenly distributed on the stone to prevent damage to the gem.
The metal of the ring must also be tough enough for the pressure. Naturally-hard materials such as stainless steel or titanium are especially common with this type of ring for that very reason. When it comes to softer metals, the jeweler must harden the metal with an alloy for it to handle the amount of pressure in a tension ring. This is the case for tension rings made out of gold, for example.
To create the design, the gem is spring loaded into the ring. On either side of the gem, the ring has grooves to hold the gem into place. Unlike other types of rings, tension rings are not as easily resized due to the nature of the design. Furthermore, the exact stone that a customer chooses will change the exact tension setting required. Thus, a manufacturer may only create tension rings after a sale, using a computer to calibrate the tension and cuts required to hold the stone firmly in place.
The result is a gem that appears to almost float in air between the parts of the rings; although, it’s actually fitted perfectly. The design has been used since 1979, when it was first marketed by the German jeweler Niessing, which sold their first tension ring as the “Spannring.” Now, consumers can purchase tension rings from a variety of manufacturers and retailers. Tension rings make beautiful fashion rings, but the solitary gem also makes this type of ring appropriate for an engagement.