Washboards date from only about the 1890s. Many sizes were made with metal or glass surfaces. Most can be purchased for less than $30 from antiques dealers, but those with advertising and unusual features command the highest prices.
Materials
The first commercial washboards were introduced about 1890, and soon the wooden scrubbing surface was replaced with textured zinc, or more rarely brass or copper. Designs with "blued" steel surfaces to prevent rust command prices close to $100 in 2010. Glass came into use during World War II, when metals went to the war effort.
Premium Factors
Advertising, such as for soap, or unusually large or small size raises the value of a washboard. Some of the more expensive collectible boards have metal soap trays.
Dating a Washboard
Some 10 companies were producing washboards in the U.S. in the early 20th century, including the National Washboard Company (the largest and therefore most commonly seen), the Cleveland Washboard Company and the Superior Washboard Company.
Since the 1970s, the sole survivor is The Columbus Washboard Company. Its Bear Easy model has been made since 1907. They had 22 brands in the 1930s, and five of them persisted into the 1980s: Dubl Handi, Maid-Rite Silver, Maid-Rite Brass, Sunnyland and Crystal Cascade.