LONDON, Nov. 27 (UPI) -- British scientists using modern imaging techniques have revealed the secrets behind the strength of some ceramics made during the Middle Ages.
Marcos Martinon-Torres and colleagues at University College London used electron microscopy and X-ray diffraction to study the ceramics made in Hesse, Germany, and sold across Europe during the late Middle Ages.
The researchers say the features of the ceramics' microstructure reveal they have something in common with tough modern ceramics, which would account for the superior quality and resistance of the medieval material.
The scientists found the ceramics' structure is a matrix and they also discovered residues from the decomposition of kaolinite at extremely high temperatures, unusual in Europe for fired pottery.
But the key ingredient discovered was mullite, an aluminum silicate widely used in today's ceramics that made the pots very strong and stable.
The researchers conclude although the potters would have been unaware of the mullite, it was probably produced by adhering strictly to a successful recipe that remained unmodified and unpublicized for centuries.
The research appears in the journal Nature.
