How was this made?
The Chertsey tiles were made with earthenware clay, both red and white. A stamp is pressed onto the red soft clay about 1 cm deep and white slip clay is applied to fill in the hollow impressed design. The tile is left to dry and excess white clay is scraped off. A wooden bat is placed on the surface of the tile and then struck down with a mallet. This process served to consolidate the inlaid white clay and break down the surface level clay so that the face of the tile was smoother.
The tile is trimmed to shape, and then moved to a drying space. Often these spaces would be outdoors, which served to explain why some tiles show footprints of small animals. Important tiles were dried in a shed. Certain tileries were unheated, but some had well-ventilated drying sheds with slatted sides that could be either opened or closed depending on the season at hand. Some medieval drying sheds would even have shutters, because it was crucial that the drying process wasn't hindered by the wet-weather season.
A lead glaze is applied to the surface of the tile to create a golden and shiny surface. The tile is fired in a kiln. The differences in the coloring of the final finished tiles is caused by the amount of oxygen present in the firing process within the kiln. A shortage of oxygen creates darker greens and browns which comes as a contrast to the brighter reds and oranges.
The diagram of the kiln shows its internal construction. Unused clay at the end of season would often be reused as rebuilding material for the kiln. The diagram on the left shows a semicircular tool used to scrape the excess clay off the face of these tiles. The picture that accompanies it on the right of the page shows more materials discovered in a medieval English tiler's workshop.
The Black Death had a profound impact on the tile industry. Craftsmen died during these tumultuous times, and those who remained would demand higher wages alongside raising the prices for their products.