5 mm coaster, 10x10 cm square. Prints in two colors, works great if you're equiped for dual color layers. I recommend printing face down to have better feeling and smoothness of the coaster. I printed it in PLA with 0.4mm nozzle diameter.

If you have only one extruder and are comfortable with splicing filament, I could send you the gcode I used and the length of each color segment to splice the filament.