what you think you know, for you might be wrong; and the correction might teach you something.
I had always thought that the ornamented bronze disk found on the belt of the Egtved Girl was unique to that find. Tonight, I learned that I was wrong. Another bronze disk that was nearly identical in size, shape and incised decoration was found in the grave of the Borum Eshøj woman, as the photograph of the grave find from the National Museum of Denmark makes clear. The similarity cannot be explained by age, since the Egtved Girl is estimated to have been in late adolescence and the Borum Eshøj woman to have been between 50 and 60 years of age--likely past childbearing. (A picture of the Egtved find is here).
The similarity I see, other than sex, is the fact that the two women appear to have died within 20 years of each other. The wooden coffin the Egtved Girl was found in was dated to about 1370 B.C.E., while the coffin of the Borum Eshøj woman was dated to 1350 B.C.E. Maybe, during that period in that part of Denmark, all women -- or perhaps all women of a certain rank, since each of the women also had a bone comb of identical design and a fair number of grave goods -- wore such a disk on their belts, and only the type of skirt they suspended changed with age.
I find myself fascinated by the similarity--and curious as to how many other graves we don't know about may contain evidence of the same fashion.
EDIT: The link I got from m_nivalis shows more than a dozen similar beltplates--all from Sweden! I wonder whether there are Norwegian examples as well. Thank you again, m_nivalis!
EDIT: The beltplates in the Historiska Museet in Stockholm that m_nivalis pointed out all come from southern Sweden (Skane, Halland, Gotland)--which makes sense since those parts are relatively close to Denmark. Interesting!