Instructions
Turn the piece of Blue Flow dinnerware over so that the bottom of the object is visible.
Look for an impressed mark on the bottom of the object. Sometimes the marks were imprinted with a colored ink. More frequently, however, the writing is simply an indention in the object itself.
Look for the name of the manufacturer, company logo and the city and state the object was manufactured in. All of these items are not always present, but there is usually at least one of them. If the object contains a symbol, but no location, then it most likely dates prior to 1890. After this date the U.S. required all imported china and ceramics to contain a country of origin.
Compare the stamped company logos on the plate with images from antique pottery resources such as Figurines-Sculpture.com. This is a useful way to identify the age and country of origin of Blue Flow ceramics when there is no writing on the piece other than a symbol.