The Quality Stamp Company of East Liverpool, Ohio produced backstamps and decorative pieces for many of the potteries in the area. Shown below are just a few examples of stamps made for the Homer Laughlin China Company, Edwin M. Knowles China Company, Taylor, Smith & Taylor Company, and Harker Pottery. The rubber stamps were created from engravings on metal sheets.
Rubber stamps made for dinnerware
The rubber stamps would be put onto handles, rollers, or machines to decorate or mark dinnerware. This included over glaze stamps using gold and platinum decorations. In the case of rollers, the design was rolled onto a colored glaze then onto paper. The paper was then applied to the pottery thereby transferring the design. This technique is commonly called "underglaze transfer." See this page for more TS&T's Underglaze Treatments.
The Quality Stamp Company is still open in East Liverpool and operates under the name, Innovative Ceramic Corporation. Their web site can viewed by visiting this link.