Abstract: A thermoformed plate having a rim adapted for embossing thereon a decorative pattern is provided. The rim has a generally curved profile which eliminates stress concentration points, providing greater stiffness and strength to the plate. A dual member mold useful in the production of the plate is also provided. The mold has corresponding male and female members, and contains an interchangeable annular insert in that portion of the surface of the male mold member that defines the rim of the plate. The desired decorative pattern for the plate is contained on the annular insert, allowing changes to be made in the rim pattern of plates produced by the mold without the need to replace the entire mold.