Just as a point of interest I have a 1900 ish Temlett seven string
banjo , which has a brass body (Silver plated when it was new) and
some nice inlay up the neck . I bought this beast in the sixties and took it in to Clifford Essex for a rehead etc . The old guy who ran C E 's shop told me it should be tuned the same as a five string with a low C and G for bass runs for song accompaniment .