The engagement ring is given when you decide to get married. It is worn during the engagement period and typically stays on the finger after the wedding, often together with the wedding ring.

In terms of design, the engagement ring is characterised by having one clear focal point. The classic version is the solitaire, where a single diamond sits raised in a setting so that light can reach the stone from several sides. A round solitaire ring is the most recognisable expression within this category, but brilliant-cut stones are far from the only choice.

The shape of the centre stone changes the entire character of the ring. The oval shape appears elongated and soft, the marquise shape is pointed at both ends and striking in its expression, the pear shape combines the two, and the cushion shape has rounded corners and a calmer play of light. An oval solitaire ring and a marquise solitaire ring give two completely different impressions, even though the setting is the same type.

Some choose a design with several stones instead of one. In the trilogy design, a centre stone is flanked by two side stones, giving more width and play of light across the finger. An oval trilogy ring is an example of how three stones can be combined in a unified expression. There are also smaller versions where the side stones are modest and the centre stone still dominates.

Pavé design means that the ring band is set with small diamonds placed closely side by side. It adds extra sparkle all the way around the finger and works both as a standalone design and as a frame around a centre stone. A round pavé ring shows how pavé details can carry an entire design without a large centre stone.

The wedding ring is placed on the finger during the ceremony and is intended as the piece of jewellery that is worn constantly. Durability and comfort are therefore prioritised over effect. The ring typically has a lower profile so it does not catch on clothing, and it is more often symmetrical all the way around.

The classic wedding ring is a smooth band without stones. It comes in gold and white gold, and the width is chosen according to hand and taste. Many couples still choose this form because it is neutral and lets the engagement ring stand out.

An eternity ring has diamonds all the way around the ring band. This gives an even play of light no matter how the ring turns on the finger, and the design is used both as a wedding ring and as an anniversary ring. A large eternity ring has relatively large stones, while a tiny eternity ring is more discreet.

A half eternity ring has diamonds halfway around the ring band, typically on the upper half. The lower part is smooth metal, which makes the ring more comfortable to wear together with other rings. A medium half eternity ring is an example of a design that lies between the completely smooth band and the eternity ring.

The word alliance ring is used in Danish jewellery language for a ring with stones set in a row all the way around. In practice it often means the same as an eternity ring. Both terms are used for rings worn as a wedding ring or as a supplement to the other rings on the finger.

The table describes general tendencies, not fixed rules. Some choose a simple ring with a small stone as an engagement ring, and others choose an eternity ring with large stones as a wedding ring.

In Denmark, the wedding ring is traditionally worn on the ring finger of the right hand, while the engagement ring is often moved to the same finger after the wedding. Practice varies, however, from family to family and from country to country, and today many people wear the rings whichever way they think looks best.

When two rings need to sit side by side, the profile of the rings matters a great deal. An engagement ring with a high setting can create a small gap next to the wedding ring if the wedding ring is completely flat. A slightly curved or narrower wedding ring sits closer. Some therefore choose to wear the rings on separate hands instead.

The choice of metal also plays a part. Rings of the same karat and the same colour wear more evenly against each other, while a combination of gold and white gold gives contrast, which is exactly what some are looking for.

It is becoming more and more common to choose two rings – one engagement ring and one wedding ring – because they mark different moments. At the same time, some choose to make do with a single ring, either because they prefer a single ring on the finger, or because they want to spend the entire budget on one piece of jewellery.

If you choose one ring, it can be an engagement ring that continues to be used as a wedding ring, or a single ring bought in connection with the wedding. This does not change the ring's meaning, but it does change which design makes the most sense in everyday life. A ring that needs to serve as both should have a profile that can withstand daily use.

Diamonds appear in both types of ring, but in different amounts and sizes. In the engagement ring the stone is often the central element, while the diamonds in the wedding ring are typically smaller and distributed across the ring band.

Diamond is the hardest known natural material and ranks 10 on the Mohs scale. This is one of the reasons why diamonds in particular are used in rings that are worn daily. The weight of a diamond is stated in carats, where 1 carat corresponds to 0.2 grams.

Lab-grown diamonds are chemically, physically and optically identical to natural diamonds. They are produced either by HPHT (High Pressure High Temperature), where carbon is subjected to pressure and heat corresponding to the conditions deep within the earth, or by CVD (Chemical Vapor Deposition), where carbon atoms are deposited layer by layer onto a thin diamond wafer in a chamber with carbon-containing gas. The result is a real diamond with the same hardness and the same light refraction. It is not possible to tell the difference between lab-grown and natural diamonds with the naked eye, and distinguishing them requires specialised equipment.

This means that the choice between lab-grown and natural diamonds is first and foremost a question of how large a stone you want within your budget, and which design you are aiming for.

The setting is the way the stone is held in place, and it affects both the expression and everyday use.

In a prong setting the stone is held by small metal claws, typically four or six. The advantage is that light can reach the stone from several angles, giving more sparkle. The disadvantage is that the setting sits higher, and that the prongs need to be checked at regular intervals.

A bezel setting encloses the stone with a rim of metal all the way around. The stone sits lower and is protected by the metal, which makes the setting practical for rings worn constantly. The expression is more understated, because less of the stone's side is visible.

In a pavé setting many small stones sit closely together, held by small beads of metal. It is typically used on the ring band and gives a continuous surface of light rather than one single focal point.

The decision about what the engagement ring and the wedding ring should be is connected to how the rings are going to be used. A person who works with their hands will often benefit from a low profile on both rings. A person who rarely takes their rings off may benefit from choosing a setting that protects the stone.

Some buy both rings at the same time so they match in metal and width from the start. Others buy the engagement ring first and find the wedding ring afterwards, once it is clear how the two should sit together. Both approaches work, but if you buy the rings separately, it is worth keeping the engagement ring's profile in mind when choosing the wedding ring.

Finally, jewellery outside the ring category can play a part in the overall picture. Some couples choose a pendant or a pair of ear studs as a morning gift, for example a solitaire pendant or a pair of prong studs, so that the diamonds recur across several pieces of jewellery.