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Definitions – Part 1

Happy New Year Everyone – thought we could start the year off with some definitions this is part 1 with part 2 on Colours next month – this may be information that you already know but hoping that it will be useful to those who are not so sure.

What’s in a Name Part 1

Pearlware is a type of earthenware pottery that was developed in the late 18th century as an evolution of creamware. It gets its name from the pearly brightness of its glaze, an effect that was achieved by adding small amounts of cobalt oxide to the otherwise slightly yellowish glaze – in effect “bluing” the otherwise cream-coloured final product. 

 The Blue and White Bourdaloue is in Pearlware

The development of pearlware marked an important step in the history of ceramics, providing an aesthetically pleasing alternative to creamware and paving the way for further advancements in ceramic technology. Because of the blue-tinted effect, it is sometimes confused with flow blue by novice collectors.

Pearlware is known for its smooth and finely potted surface, as well as its ability to showcase intricate moulded or painted decoration. It was a popular ceramic ware during the late 18th and early 19th centuries, particularly in England.  Though his personal preference was for the elegance of the creamware that he pioneered, renowned English potter Josiah Wedgwood played a significant role in the development and promotion of pearlware.  However, he believed that once the pearlware fad had run its course, the popularity of Creamware would return.  Instead, as better sources of raw materials were found, less and less cobalt needed to be added to glazes to counter the colour of inherent impurities, and as the second half of the 19th century progressed, pearlware became “whiteware.”

It is interesting to note that contemporary invoices almost never mentioned either “pearlware” or “china glaze” (the term originally used for “pearlware”).  At the time, the focus was instead on the types of decoration.

The blue haze can be clearly seen in this photograph of the underside of the Bourdaloue.

Transferware is a type of ceramic or pottery decoration technique that involves transferring a design onto the surface of the ware. This technique became popular in the late 18th century and gained widespread use in the 19th century. The process typically involves using an engraved or etched copper plate to transfer a printed design onto paper. The design is then transferred from the paper onto the pottery using a special ink or pigment.

Note that there is no blue haze on this piece of transferware

One of the most common types of transferware is blue and white and although it can be found in many colours blue and white was the most popular, the design is transferred onto a white or cream-coloured background. English potters like Josiah Spode and Josiah Wedgwood popularised this style. The designs often feature scenes, landscapes, or historical motifs.

Flow Blue is a style of pottery, and often a specific type of transferware, that originated in the early to mid-19th century.  Around 1840, it became particularly popular in both England and the United States. The term “Flow Blue” refers to the blurred or “flown” quality of the blue decoration on the pottery that was achieved through the intentional introduction of chemicals (flow powders) – either placed in the saggars or added directly to the glaze formulations – that caused the cobalt oxide in the decorations to volatilize when the kiln reached its operating temperature.  This volatilization moved the blue cobalt away from its original placement, creating the desired blurring or flowing effect.

To make a Flow Blue ware, a white earthenware or ironstone body is decorated with a cobalt oxide pattern that is printed on an appropriate paper or tissue. The design is then transferred onto the pottery by hand in such a way that causes the pattern to become stuck to the pottery surface.  A lead-based silicate glaze is then applied to the piece and it is then “glost-fired” to melt the glaze and affect the volatilization of the cobalt oxide design, finally producing the desired blurry effect.  The dreamy soft effect of the blurry pattern images gives the china its distinctive appearance.

Early Flow Blue wares often feature a variety of designs, including floral patterns, landscapes, and scenes inspired by Asian and Middle Eastern motifs.  Flow Blue is not only found decorated by the transfer method.  It can also be found decorated with hand-painted and cut-sponge applied designs.   Flow blue as a general style gained broad popularity in the Victorian era and became a fashionable choice for tableware and decorative items mainly in the US.  It also enjoyed at least limited commercial success throughout European countries and their colonies.

“Historic Blue” in pottery refers to a style of blue and white transferware that emerged during the early 19th century and continued until it was essentially replaced by the exploding popularity of flow blue in America. This style shares some similarities with other blue transferware, like Flow Blue, but is much darker.  It is often suggested that the rising cost of cobalt oxide encouraged the switch to flow blue, where the flow process made more efficient use of cobalt’s intense blue color.

Historic Blue transferware typically features scenes depicting historical events, landscapes, and prominent landmarks.  As with flow blue transfers,  the historic blue decorations were applied using the transfer printing process, where a design is engraved onto a copper plate which is and then inked (with an oily mixture of cobalt oxide) to then transfer the pattern onto the pottery. The term “Historic Blue” reflects the common themes of American history found on these ceramics, showcasing scenes such as patriotic symbols, significant events, and famous landmarks.

These pieces were popular during a time when there was a strong interest in historical subjects, especially those related to the young United States. Its popularity exploded after the War or 1812 and the patriotism that ensued.  Historic Blue transferware often tells a visual story, providing a glimpse into the cultural and historical context of the time it was produced.

Ironstone is a type of stoneware or earthenware pottery that is characterized by its dense, hard, and durable composition. It is named for its distinctive iron-like appearance and strength. Ironstone pottery was first produced in the early 19th century, with its origins often attributed to Staffordshire, England.  In fact, Charles Mason patented an ironstone formula in 1813 that specified a significant iron content.  As it turned out, however, it was not a particularly workable formula.  While the original for Mason’s ironstone included iron oxide, its eventual great strength and sturdiness were due to nonferrous improvements in its formulation, not iron.  The great and lasting value of “ironstone” was in the enthusiastic reception the idea received in the marketplace.  Ironstone” was a marketing success more than a manufacturing one.

Ironstone gained popularity as a more affordable and practical alternative to porcelain during the 19th century. Its production continued into the 20th century, and it was widely used for everyday tableware, serving dishes, and decorative items. Ironstone pottery comes in various patterns and styles.

White Ironstone China as we know it was first patented in 1813 by Charles James Mason in Staffordshire, England. It was an improved china harder than earthenware and stronger than porcelain. Mason’s patent lasted only fourteen years, and by 1827 several other potters had already experimented with his formulas.


Our Early Flow Blue was produced on Ironstone Pottery

Sheet Pattern

This is where an all-over pattern is applied with a sheet transfer with repeat patterning all over.

The transfer is cut to fit the shape of the item making it very economical to use as there were no requirements for placement of the transfer. Often used on children’s pottery This was used in patterns over the Victorian and Edwardian periods