This oval serving platter is in the Essence dinnerware pattern by Pfaltzgraff, produced from 1984 to 1991. It measures 14-3/4 by 10-5/8 inches high. It's in perfect condition, probably never used with no damage. Marked on the underside with Pfaltzgraff USA castle logo "14 3/4, 016, Oven & Microwave". This pattern goes well with the Blue Gazebo pieces I have listed elsewhere in the shop. The last photo shows a matching Essence baker also available.
Pfaltzgraff Blue Essence 15 Inch Oval Serving Platter