Medieval Tile Making

If you made a tile at the City Museum during the 2024 Festival of Archaeology in July or at St Bartholomew during Heritage Open Days in September, these are ready to collect from the Hyde Tavern, SO23 7DY.

Many fragments of medieval tile have been found during the community digs. These inlaid (encaustic) tiles were made from red-brown clay with a bright white inlaid slip decoration and a transparent glaze.

Inlaid tiles in Britain were popular from the 13th-15th centuries and were mostly used in monastic and royal buildings. The inlaid technique may have come from France where the encaustic tile industry was thriving from c. AD 1200.

At many events, Hyde900 has offered medieval tile workshops where replica inlaid tiles can be made using traditional methods. Although the tile only takes a short time to make, it takes several months of drying, firing and glazing before the tile is finished.

Medieval floor tile with white inlaid griffin on red clay tile, found during the 1995 excavation.

Hyde900 tile stamps

These hand-carved wooden fleur-de-lys and griffin stamps are based on medieval tile patterns found during the community digs.

Two hand-carved wooden stamps with fleur-de-lys and griffin medieval tile patterns found during the community digs

Preparing the clay

The clay is wedged to make it more malleable and easier to press into the stamp mould. If the design isn't pressed far enough into the clay, parts of the white design could be missing. Wedging also helps to remove air pockets which could affect the firing. The cross-section shows air trapped within the dry tile.

Air pockets can be seen within this raw clay tile

Creating the tile

The stamp is placed face upwards inside the wooden mould and sprinkled with fine sand to help release the tile.

The clay is then beaten down firmly into the stamp to create smooth sides and to prevent cracks.

The tile is removed from the stamp and filled with white slip.

A lady is beating the clay down firmly into the stamp mould with a wooden stick

Drying

The tiles are left in an open shed to dry slowly until they have the feel and consistency which potters call 'leather hard'. The excess slip is then hand-pared back from the upper surface of the tile to reveal the decorative image.

The excess slip on the tile is being hand-scraped by a person holding a file.

First (biscuit / bisque) firing

The clay tile is fired only when it is thoroughly dry. The kiln is heated gradually to up to 100°C to ensure there is no remaining moisture in the tile that would boil, produce steam and shatter the tile.

The temperature is then slowly increased to remove the chemically combined water which is still left in the tile. From around 500°C, the temperature is increased more rapidly to the end point of 1000°C.

The firing leaves the clay with a porous surface to which the glaze can adhere.

1st image - showing shrinkage after the first firing

2nd image - before the first firing

Washing

Dust on the tile (mostly from the dressing back of the excess slip) is washed off before the tiles are glazed.

If the tile is left dusty after the first firing, the glaze will roll back from the surface, leaving behind unglazed, or partially glazed areas.

Glazing

The tile is fired twice - before and after glazing.

1st image - the tile after the first firing with no glaze

2nd image - after the clear glaze has been brushed on

3rd image - after the glazed tile has been fired