Blue/Black Deco English 1940s Bakelite Buttons - 12 of them - 2.2 & 1.8cm

These 1940s bakelite buttons are an unusual colour - black with a blue tinge
 - not quite as black as the true black.

They are slightly domed, with a very deco design on the top.
I have them in either 2.2cm or 1.8cm in diameter.
They have a single integral shank at the back 
On their display card is printed
"Washable and Ironproof"
"Made in England" .