Philadelphia earthenware from the Columbian Pottery was advertised in the early 19th century by several Alexandria, Virginia merchants. These wares, known as Philadelphia Queensware, can be difficult to identify in the archaeological record, but examples of yellow-glazed chamber pots manufactured by the Columbian Pottery have now been identified in the collections of the Alexandria Archaeology Museum.
Magid, Barbara H.
"Promoting Domestic Manufactures: Philadelphia Queensware in Alexandria, Virginia,"
Northeast Historical Archaeology:
46, Article 10.
Available at: https://orb.binghamton.edu/neha/vol46/iss1/10