Ok. ThanksI've seen such cast-brass "tacks" (but they're bigger than a typical tack) used as decorative studs on furniture ...and also, as "skid discs" on luggage/trunks. The shaft on the disc's back was peened outward to hold the disc onto wood, metal, or thick leather. The ones on the trunk in the photo (below) don't have the same design on their front as yours does, but you get the idea.
I've seen such cast-brass "tacks" (but they're bigger than a typical tack) used as decorative studs on furniture ...and also, as "skid discs" on luggage/trunks. The shaft on the disc's back was peened outward to hold the disc onto wood, metal, or thick leather. The ones on the trunk in the photo (below) don't have the same design on their front as yours does, but you get the idea.