Pottery marks tell a story of the manufacturing process, usually with the country of origin and a logo or signature identifying the pottery, the potter and sometimes the year of manufacture. Impressions in the soft clay are not always easy to read, and a signature may look like a scribble or an imprint may not be complete. The potter may be a studio potter with little information available. With persistence and know-how, you can find a pottery maker's mark leading you to the value of your pottery.
Look on the bottom or backside of the pottery item to see the mark clearly. Hold the item to the light, since marks are sometimes faint. Use a magnifying glass. Copy the mark onto a piece of paper so you can work with it or take it with you.
Refer to a general book of pottery marks. Standards in the industry are Kovel's "Dictionary of Marks -- Pottery and Porcelain" or "Kovel's New Dictionary of Marks" and "Miller's Pottery and Porcelain Marks." Specialized books are "1,100 Marks on Foreign Pottery & Porcelain" and "1,800 Marks on American Pottery and Porcelain" from L-W Book Sales. The Kovels' books sort marks by alphabet, but also by characters like stars, circles, ovals or wreaths to make the identification process easier.
Check online by entering any written information from the mark into a search engine like Google or Yahoo to see what you can learn, or use an aggregate locator like T.S. Restoration with links to websites with specialised marks. The International Ceramic Directory and similar websites have images of marks for comparison.
Identify pottery maker's marks by country of origin. Since 1891 and the enactment of the McKinley Tariff Act, imports to the United States have the country of origin marked somewhere on the piece. In recent years, the country marks may be paper stickers, but older pottery has more permanent country identification. Once you know the country of origin, look for the specific mark within that country or continent. Books like "Marks on German, Bohemian and Austrian Porcelain" by Rontgen are invaluable to identifying European pottery marks.
Take the paper with a copy of the mark to an antiques and collectibles shop or show near you and ask a dealer for ideas or help with identification. The shop owner or show dealer may be knowledgeable or may have books available to check the mark for you. Don't give up. New books are being published as more information is available, so if you cannot find the pottery maker's mark right away, try again in a few months.