Calm vintage buttons ..the bluey grey edge slopes upwards and then swoops down into the soft cream concave centre.
The buttons are made of plastic and measure either
2.5cm - 11 on a card
2cm - 24 on a card
2cm - 23 on a crd
1.7cm - 24 on card
I found them in an old button warehouse - they're Italian - probably from the 1960s, maybe earlier.