An eternity ring is a ring with small diamonds set in a row all the way around the ring band, so that the stones form an unbroken circle without a single larger centre stone. That very unbroken row is the ring's hallmark: no matter how you turn your hand, the eye meets diamonds. In Danish this same type is most often called an "alliancering", and in practice the two terms cover the same thing.

The word "alliance" means union or bond, and that is where the ring's symbolism lies. The unbroken circle of stones with no beginning or end is used as an image of a bond that continues. That is why the eternity ring is closely linked to weddings and anniversaries, but it is also worn entirely without occasion as a piece of jewellery.

How an eternity ring is built

The basic principle is simple. The ring band is set with identically cut diamonds of the same size, placed close together in a continuous row. There is no single stone that stands out as the most important - the emphasis is on the whole and on the even line of light around the finger.

The stones are typically held in place by small prongs or by a rim of metal around each stone. The band itself is usually narrow, because the diamonds are meant to fill the surface, and the setting must be discreet enough that it is the stones you see. At Longvé the eternity rings are made in 14K gold and 14K white gold, and they come with both lab-grown diamonds and natural diamonds in the same design.

Because the diamond is the hardest material that exists, sitting at the top of the Mohs hardness scale with a value of 10, the stones withstand the daily contact that a ring set all the way around the band inevitably encounters.

The difference between a full eternity ring and a half eternity ring

The most important distinction, when talking about this type of ring, concerns how far around the diamonds sit. A full eternity ring has stones all the way around. A half eternity ring has diamonds halfway around the ring band, typically on the top half, while the underside is smooth metal.

The difference is not merely cosmetic. The unbroken row gives the full eternity ring the same look from every angle, and the hand shows diamonds no matter how the ring turns. A half eternity ring, on the other hand, has an even, smooth underside against the hand, and it can be resized more easily, precisely because the lower part is metal without stones.

If you want to see the two types side by side, Longvé gathers them under the collection eternity rings, where both the variant with stones all the way around and the version with stones halfway around are available in different sizes.

How many carats are in an eternity ring?

The total diamond weight depends on how large the individual stones are and how wide the row is. A fine eternity ring with small stones may be low in total carat, while a heavier model with larger diamonds reaches considerably higher. For reference, 1 carat corresponds to 0.2 grams.

At Longvé the eternity design ranges from fine versions to wider models. A medium eternity ring in 14K gold has a total weight of 0.80 carat, while a large eternity ring in 14K white gold reaches 1 carat spread across the entire row. So the weight tells you most about how striking the row appears, not about one particular stone.

Lab-grown or natural diamonds in the ring

An eternity ring can be set with either lab-grown diamonds or natural diamonds. The difference between lab-grown and natural diamonds lies in where the stone was formed, not in what it is. A lab-grown diamond is genuine carbon diamond, grown in a controlled environment, and has the same optical and physical properties as a natural diamond. With the naked eye you cannot tell whether a stone is grown or natural.

This means you can choose freely based on which total carat and which look you want. At Longvé most ring designs are available in both variants, so the same design can be ordered with lab-grown diamonds or with natural diamonds.

When is an eternity ring used?

The eternity ring has a long tradition as a gift ring for anniversaries and as a ring added after a wedding. The unbroken circle of stones fits that symbolism well, and it is one of the reasons the ring is often associated with milestone wedding anniversaries and other landmarks.

At the same time it is very much used as an ordinary piece of jewellery, worn alone or stacked together with other rings. A narrow eternity ring lies flat against a plain ring or against a solitaire ring and therefore works well in a collection of several rings on the same hand.

If the ring is to be part of an engagement or a wedding, it is worth knowing the difference between the two rings you often choose from. Longvé gathers them under solitaire rings with one centre stone and under the eternity line with stones in a row, so you can compare the two looks before choosing.

How to choose between a full and a half row of stones

The choice between stones all the way around and stones halfway around is mostly about how the ring will be used day to day. A full eternity ring gives diamonds around the entire circumference and looks the same from every angle, but the row of stones on the underside is met by the hand with every grip.

A half eternity ring with a smooth underside sits more softly against the neighbouring fingers and against another ring on the same finger, and it is easier to resize. For many it therefore becomes a question of whether the ring is worn on its own or stacked closely with other rings. Both are available in Longvé's rings, so you can hold the two types up against each other in the same metal and size.