Q: I have a vase that's marked "I.V.W." inside a diamond. Can you tell me who made it and how old it is?

A: Some sources speculate that the mark was used by Van Wickle pottery, which operated in Brick, New Jersey, from 1824 to 1838. However, most sources say the initials "I.V.W." stand for "ivory white ware" and were used about 1880 by Jersey City Pottery of Jersey City, New Jersey. The middle letter should have been a "W," but Edwin Atlee Barber suggests in "Marks on American Potters" (published in 1904) that the mark was "prepared hurriedly" and the mistake was never corrected. Jersey City Pottery was operated by several different companies from about 1825 to 1892. It was incorporated as Jersey Porcelain and Earthenware Co. in 1825, then became Jersey City Pottery in 1827. Two years later, following a short closure, it was reopened by David and J. Henderson, who renamed the firm American Pottery Manufacturing Co. in 1833. The name was changed to American Pottery Co. in 1840. But after other ownership changes over the next decade or so, the company's name reverted back to Jersey City Pottery. It was also known as Rouse & Turner, for John Rouse and Nathanial Turner, the last owners of the pottery. The buildings were torn down in 1892.