Here is a fine example of an oval antique oyster plate made by Union Porcelain Works of Greenpoint, New York, the first American company to produce oyster plates. The standard UPW mark is on the back along with the patent date of Jan 4. 1881. We also find on the back a mark indicating that the plate was sold retail by Richard Briggs of Boston, a major retail store at that time. The UPW plates have always been known for their nautical decorations and variety of colors. Indeed it would be hard to find two of their plates identically alike. There are several closeup pictures which show the plate's attributes. There is a small sliver missing on the underside rim (see last picture), not visible from the top. This plate is one of three sizes produced by UPW. The company made a large oval plate and a round plate. The longer dimension of this plate is 8.5 inches and the smaller dimension is 6.5 inches.