A 19th century earthenware kiln in the midwest differed little from those of medieval Europe.
 
Redware kitchen bowl
Springfield, Illinois ca 1840
Redware pot, with lead glaze worn away from base of vessel, exposing red clay beneath
Traditional slip decorated pie plate, circa 1800
Salt glazed stoneware pot,
circa 1830.
Albany slipped stoneware
circa 1870
Yellowware jar, made in Alton, Illinois
circa 1855
Yellowware table bowl made in
Cincinnati, Ohio circa 1840
Stoneware jug, circa 1840.
Redware pipkin, circa 1850.
UNDERSTANDING UNREFINED CERAMICS: Common Types and Terms, 1790-1850 Robert Mazrim 2008 (Excerpted materials from Mazrim’s “Seminar in Historical Archaeology: Samples, Artifacts, and Consumer Goods” Illinois State University, Graduate Program in Historical Archaeology, Spring 2008) This article is designed as an overview of the basic types of unrefined ceramics in use in the Midwestern United States between 1790 and 1850, with an emphasis on the American-made products that dominated the market by the close of the 18th century. While the market for refined earthenwares for the table was dominated by British potters during the period, the origin of unrefined wares - or “crockery” - was most often a domestic one by the late 18th century. Most of these products were designed for the kitchen, as utilitarian storage or cooking pots. Unrefined tablewares were still in use as well, but their importance on the American table declined rapidly during the early 19th century. It should be noted that, unlike the mass-produced, internationally-marketed British Queenswares, unrefined crockery was far more regional in nature. While a table set in Philadelphia would most likely include pearlwares similar to those on a table in New Orleans, this is not the case with kitchen crockery. These products were of low value and yet costly to ship, and thus were often made very near to where they were sold. As a rule, crockery also tends to more closely reflect the kitchen habits and customs of a particular region or ethnic group, and therefore local potters could best serve local kitchens. This, however, also depended on the presence of the appropriate potters’ clays. Unrefined wares are generally classified according to WARE TYPE first, and VESSEL FORM second. Decoration is of much less importance in categorization, as most unrefined wares were undecorated. Archaeologists recognize three basic unrefined ware types: REDWARE, STONEWARE, and YELLOWWARE. Each of these products was made of a distinctly different clay, and was fired at different temperatures in separate kilns. Generally, potters specialized in only one of these three types of products. REDWARE: Redware is a low-fired earthenware, usually made of a soft, red clay coated in a clear lead glaze. Because most of the clays used in this country were brick red, the term “redware” is generally applied to this form of this crockery. In Europe, however, many such clays are not red, and the same products are simply known as “lead glazed coarse earthenwares”. It should be pointed out that in this country too, some makers of lead glazed coarse earthenware used less-than-red clays, resulting in pots that can look yellowish. This does not make those pots “yellowware” – they are all simply part of the lead glazed coarse earthenware (“redware”) family. Redware clays are abundant and easily accessible in the Midwest (being basically the same clays used in soft mud brick), and can be fired at reasonably low temperatures. The craft of turning and firing lead-glazed is an ancient one, and the first to be imported to North America. The kilns, production methods, and wares found at an early 19th century redware pottery kiln would have been quite familiar to a potter working in 16th century Europe. Nearly all redware products were coated in a lead slip glaze, in order to render the vessels waterproof and easier to keep clean. The glaze could be “clear” (making the vessel a yellowed or darker shade of the clay color beneath), or could be colored with mineral additives such as manganese or copper, resulting dark brown, black, or green finishes. While many 18th century redware potters in eastern communities (such as those in central Pennsylvania) decorated their pottery with festive yellow, white, and green slip decorations, these traditions had faded considerably by the second decade of the 19th century. Even during the heyday of those traditions, most the of the utilitarian pots on the potter’s wagon were not decorated. STONEWARE: Stoneware clays produce much more durable vessels than redware clays, but they are harder to find, and require a higher firing temperature. For this reason, redware was usually the dominant form of crockery in newly-settled communities. Stoneware products were more often imported from other regions of the country. The clays used in stoneware products are usually a medium to dark gray color. However, when under fired, they can appear pink to salmon in color, and small fragments are sometimes mistaken for redware when identified only by the color of the clay. The most common method of waterproofing stoneware was with the use of a salt glaze, which was created by vaporizing salt in the kiln. This could only be accomplished in high temperatures, thus there is no such thing as salt glazed redware. Conversely, lead glazes used on redware would evaporate if used in the high temperature stoneware kilns. Sometime in the 1830s, a brown clay slip began to be used in combination with a salt glaze to produce “Albany slip” wares. These chocolate brown glazes appeared as thin, matte finishes on the interiors of bowls and pots when first introduced. By the 1850s, many forms of stoneware were coated inside and out with a thick, glossier form of Albany slip. The familiar cobalt blue painting and stenciling on stoneware pots did not become common in the Midwest until after 1860. YELLOWWARE: Yellowware is a ceramic type developed in the 19th century that has attributes of both refined and unrefined products. Unlike redware and stoneware, most yellowware products were not thrown on a wheel in small-scale pottery shops. Instead they were usually mold-made in larger factories, and in more uniform vessel shapes. However, yellowware products are classified as unrefined wares due to their most common forms and functions: that of utilitarian kitchen bowls, baking dishes (“nappies”), and chamber pots. Before 1850, yellowware tablewares (such as small bowls and pitchers) were also common, making it difficult to categorize this unique ware. Yellowware is easily distinguished from other unrefined ware types by its fine-grained, yellow-buff fabric, crisp vessel shapes, and very clear, uniform glazes. Yellowware was often decorated in blue, brown or white bands, and early in its history, with dendridic “mocha” patterns (see the refined earthenware tutorial). Another common decoration on yellowware was brown manganese dripping or splotching, which by the 1860s, led to the all-brown “Rockingham” pottery. Yellowware was made both in England and the United States, but much of the yellowware found in the Midwest was probably made in Ohio-Valley potteries. VESSEL FORMS: Unrefined vessels made between the late 1700s and the mid 1800s can generally be placed into one of three basic categories: STORAGE: Open mouth pots, shouldered jars, and jugs are the most common forms of storage vessels, in redware and stoneware. FOOD PREPARATION: General purpose kitchen bowls were made in all three ware types, but only redware and yellowware could withstand the thermal shock of being placed in hot coals or on early stovetops for cooking. So vessels such a pie pans, pipkins, and bean pots were made of redware. After 1840, yellowware had generally replaced redware for such purposes. Stoneware churns and redware milk pans are also common. FOOD SERVICE: By the late 1700s, traditional redware tablewares had largely been replaced by popular English refined earthenwares. In some parts of the country, some potters still found buyers for decorated redware platters, or simple plates, table bowls, and pitchers. By 1840, however, redware had been confined to the kitchen, and only a few yellowware tablewares were in use. Unlike their European counterparts, American stoneware potters made very few tablewares. Some redware and stoneware potters also made PRODUCT BOTTLES, for beer, soda water, ink, or mustard, as well as TOILET WARES such a chamber pots. Product bottles became more common after 1840, while lead glazed chamber pots have been made as long as there have been redware potters.
Medieval European chamber pot,
copper green glazed earthenware.
Stoneware rim styles, Morgan County circa 1850