Bull Exper Firing Group 3

X-ray diffraction, atomic absorption and SEM analyses.

A complex updraught kiln, made of pre-fired tiles, was based on Repton Priory kiln. Fired with fuel on support bars it reached 1300 C in 8 hours (normally 12-14h). Inlaid tiles were successfully made with local clay; working properties are analysed in six appendices.

Three different types of superstructure were tested on a common substructure of a pair of grated fireboxes placed either side of a central combustion chamber. The consistent performance and product leads to the suggestion that the potter, rather than the kiln design, is the main determinant of quality.

Dies of bone, wood, and chalk were impressed on partly-dried vessels and on trial discs. Fired in a bonfire, all fabrics were successful, but chaff-temper had not burnt out.

In some circumstances, particle orientation shows better in tangential thin section and is preferable to x-radiography.