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 brooches in Norwegian. Each kind of brooch has its own distinctive name, some of which date back to the Middle Ages.

A rosesølje is a ring brooch made from six open kidney-shaped motifs arranged in a ring, made from filigree or cast imitation filigree. This pattern was first used in Norway in the Middle Ages, and has continued in use, almost unchanged, up to the present day. Paradoxically, the oldest surviving brooches are made of imitation filigree. True filigree brooches are no earlier than the mid-18th century, and the most elaborate, like this one, usually date from the 19th century. Rosesøljer are particularly common in south Norway, in the region centred on Telemark.

This brooch probably comes from Telemark, or Sigdal and Eggedal. It is inscribed on the back with the letters BTF in cursive script. Norwegian women frequently marked their jewellery to show their ownership. It was bought for 15 shillings at the International Exhibition, London, 1872.