3-3.5 , Q.1 Blue : Natural Sliced Dyed Agate Coaster with Rubber Bumper Set of 4 (Q.1 Blue, 3-3.5"), By JIC Gem

Are they gold on the edges?

How thick are the coasters? (with and without rubber tips)

What size or dimension is best for a glass or mug? Honestly just want them for decorative purposes but still big enough for a glass

How do we email the seller? I am not satisfied with my purchase!