Curved Grooves Pewter 2-hole "Dora" Button, 7/8" / 22mm USA Made, #FJ-56
Thin and not domed, 3mm holes, and the silver color is fairly shiny so the light catches the grooves. As the light changes, the grooves and the background trade from light to dark. Lead-free pewter, made by Danforth Pewter in Vermont. Limited supply. $1.50 each.