These glass products from Xeonix use the latest technology in polyester glass coatings with excellent weatherability, chemical resistance, and abrasion resistance. The finish is baked onto the glass in a huge $80,000 oven. Actual metal powders are used to produce the pewter and copper finishes. The Copper Seal Altar Plate is 12 round x 3/16 and features a fused copper design on beveled glass.