Four sets of bear claws around the edge. 5/8" diameter, softly domed, shank loop opening is around 3mm.  One of our favorites.  Nickel silver concho button from New Mexico. Artisan made. Best quality.  Limited supply. This button maker has now retired, so once these are gone, they're gone.

We also have this button larger, 3/4",  in another listing for WN34