The ring brooch was the most important piece of jewellery in Norwegian traditional dress. Ring brooches can be circular or heart-shaped, and their design dates from the Middle Ages. They differ from modern brooches in the way they fasten. The wearer pulls the cloth of the garment through the central hole, and then spears it with the pin. The greater the strain on the pin, the more secure the fastening. Ring brooches were worn throughout Norway in the 18th and 19th century. Their shape and pattern varied by district and use. They were worn by men, women, and children.

There are well over 50 different names for ring brooches in Norwegian. Each kind of brooch has its own distinctive name, some of which are medieval in origin.

A bolesølje is a large ring brooch decorated with six raised circular mounts. It takes its name from a medieval cylindrical box, called a bole. Like most Norwegian brooches, its design is medieval, but it is the only kind of brooch which was never made anywhere else. It is unique to Norway. Brooches like this were always expensive, because of their size and weight. In the 18th century they were usually cast, but by the 19th century most were made of filigree. Bolesøljer mainly come from the south of Norway.

This brooch is one of the oldest kinds of filigree bolesøljer. By the 19th century the back plate was completely hidden by filigree, and the central hole had shrunk to almost nothing.