Vintage Cork and Plastic Coasters Set of 6 Blue, Green, Yellow and Red

These were included in an estate sale haul - they do not appear to have been used. If they were, it was very gently. There are 2 green, 2 blue, 1 yellow and 1 red They are a hard plastic that are slightly transparent with a thin cork insert. They are marked Taiwan on the bottom. They measure 4-1/4" diameter from edge to edge.