The most numerous category of ceramics visible on the surface of the Jacksonville "Blue China" wreck site were 358 British slip-decorated utilitarian earthenwares representing 37.3% of the total pottery. They comprise an assortment of bowls, jugs and mugs referred to in contemporary sources as "dipped" or "dipt" ware. A sample of 48 examples was recovered for study.
The excavation produced two banded slipware mugs in two different sizes corresponding to one-half and one full pint capacities. These two examples are decorated with some combination of wide blue and/or gray bands in combination with six or eight brown stripes. Simple slip bands as seen on these mugs were the most common slip decoration of the period. No maker’s marks have been detected.
First produced by Staffordshire potters in the late 18th century, these generic whitewares enjoyed a long period of popularity and were among the least expensive imported decorated earthenware available to American consumers from the 1780s well into the 1850s.
A number of features related to production changes that took place in the 19th century independently confirm the date range of 1850-60 for the dipped wares found on the Jacksonville "Blue China" shipwreck, while additional artifacts from the site narrow its most plausible date of loss to 1854. One was a reduction in color choices. Originally slips comprised a variety of earth colorants. Iron oxide produced reds and rusts, and manganese produced black and dark browns. Cobalt oxide yielded blue, copper oxide green, and antimony and uranium yellow. The lead glaze that vitriﬁed the objects also enhanced these earth colors. When the toxicity of many of these substances became realized, they were removed from circulation and became obsolete. As a result, the colors found on dipped wares in the second half of the 19th century are predominantly black, blue, gray and white and lack the earlier vitality.