Weddings and rings seem to be inseparable. Nearly every culture uses a ring of some sort to signify marriage and the traditional of wearing it on the third finger of the left hand dates right back to the Romans.

The engagement ring is the first ring a couple buy. It is usually a dress ring of some value, worn by the fiance on her wedding ring finger. The man does not have an engagement ring but will often wear a signet ring on the same finger. He may alternatively wear his wedding band on the third finger of his right hand until the marriage ceremony, then swap it over. Incidentally, the engagement ring should never be worn at the marriage ceremony - it is said to be very bad luck and bad form to do so.

There is no hard and fast rule about the engagement ring. The man may have a family ring he wishes to hand on to his future bride. Alternatively, you can buy an antique ring, a modern one or have one specially made. The stone may be of any type - even pearls are acceptable. Diamonds, however, are the favourite choice. When choosing a diamond, get expert advice and always remember the four Cs: carat, cut, clarity and colour.

If the rings are to be specially made, couples may, with the help of the jeweller, submit their ideas as a sketch. They may even ask to have an older ring of sentimental value or their own stones used in the design. It may come as a surprise, but it isn't always more expensive to have a ring made.

If there is an art college in the vicinity, it may even be possible to supply the raw materials for one of the senior students to design and make up. This is often a very successful idea and it is worth making enquiries.

The wedding ring, of course, will also have to be chosen if it is not to be part of a set. It is supposed to represent eternity and for this reason should be an unbroken band of a plain design. These days again, traditions are changing and a continuous design all round is now acceptable.

Gold of the best quality affordable is the usual metal chosen, though some couples are now turning to platinum. If gold is chosen, it is worth making sure it is of the same carat or purity as the engagement ring. If it is not, the less pure or harder gold will wear away the other when they are worn together.

If the man is to have a wedding band as well, it should match his bride's, so it is only sensible to buy the two together even though, traditionally, the bride-to-be pays for it.

A final thought. Engagement and wedding rings can be very expensive pieces of jewellery. It is only sensible to insure them as soon as they have been bought. Your insurance broker will advise or the jeweller may be able to sell you a suitable policy when you buy them.