About 34mm diameter with slight dapt, I have loved this piece for so long. Center hole is 3/32mm, and our rivet-washers fit it nicely, if you'd like to attach or fasten it to something else---another stamping with a rivet (or swedge hole as it was called in the stampings trade). Brass made from vintage tooling, Silverware Silverplate. Sold by the piece.
Brass Pinwheel Leaf Stamping, Silverware Silverplate, Open Floral Sprig for Riveting, 34mm