This week we go back to our series on early historic ceramics often recovered on archaeological sites and their significance in the historic and archaeological record. Past posts have discussed Jackfield (1745-1790), Scratch blue (1744-1775), Slipware (1675-1770) and Creamware (1762-1820) ceramics. Colonial ceramics of the 17th and 18th centuries are typically divided into three categories: Earthenware, Stoneware, and Porcelain. These categories are derived from the clays used in manufacture as well as the firing techniques.
Tin-glazed ceramics, often called delftware, are a soft-bodied earthenware ceramic first produced in northern Europe in the early 1600’s. Found earlier in other locations, tin-glazed ceramics represent attempts throughout the Middle East and Europe to copy porcelains produced in China during the 15th and 16th centuries. They were also the first white, painted pottery produced in England (Diagnostic Artifacts in Maryland). Known as tin-glazed due to the addition of tin-oxide to the lead glaze, these ceramics have a thick white glaze referred to as tin enamel, readily identified by its eggshell appearance.
|Tin-glazed earthenware salt dish, found at the
Byrd Leibhart site (36Yo170). Photo from the Section of Archaeology, The State
Museum of Pennsylvania|
|Tin-glazed earthenware bowl, found at the Market Street site (36Ph1). Photo from the Section of Archaeology, The State Museum of Pennsylvania.|
As with most types of ceramics, tin-glazed earthenwares were decorated using various techniques, each coming and going in and out of popularity at various times. Since the date range when each of these techniques was used can be identified, they are a useful tool for dating archaeological sites and features. Though there are a number of different design methods used on tin-glazed earthenwares, a few of the more common styles found on Pennsylvania sites include the following.
|Sponge decorated tin-glazed earthenware fragments, found at Fort Hunter (36Da159), 2020. Photo from the Section of Archaeology, The State Museum of Pennsylvania.|
Sponge decorations are created by the application of a cobalt oxide using a sponging technique. This decoration looked like blue sponging after the vessel was fired and dates between 1708 and 1786. A similar looking decoration called powdering occurred when the vessels are powdered in manganese, which results in a purple-sponge decoration after firing. Powdering decoration was used on tin-glazed ceramics between the late 17th and early 18th centuries.
|Oriental landscape motif tin-glazed earthenware mending fragments, found at Fort Hunter (36Da159), 2020. Photo from the Section of Archaeology, The State Museum of Pennsylvania.|
Fazackerly decorated tin-glazed earthenware fragment, found at Fort Hunter (36Da159), 2020. Photo from the Section of Archaeology, The State Museum of Pennsylvania.
Blue circular floral motif on tin-glazed earthenware, found at Fort Hunter (36Da159), 2020. Photo from the Section of Archaeology, The State Museum of Pennsylvania.
These are just a few of the different decoration styles found on tin-glazed earthenwares, but they each are useful for archaeologists in identifying site function and time period. By the mid-18th century, creamware was in production and as a more refined and durable earthenware this began to replace tin-glazed earthenwares. By the late 18th century, production of tin-glazed earthenwares were in significant decline.
We hope you will continue to follow our blog to learn more about the incredible ceramics that have been recovered by archaeologists from across the Commonwealth. The preservation of these objects provides a personal glimpse into the lives of early colonists and of the potters who produced them. German and English immigrants who became potters in Philadelphia, Lancaster and York developed their methods and refined the clay available locally to produce ceramics that would replace those from Europe and led the way for many artisan crafts throughout the colony.
Advancements in science have allowed archaeologists to analyze clay sources and trace them to regions and in some cases potters. Archaeologists have the unique ability of finding the stories of everyday life through the evidence of the past, even if it is only a broken piece of pottery.
Hume, Ivor Noel
1969 A Guide to Artifacts of Colonial America. University of Pennsylvania Press, Philadelphia (reprint)