Gothic green glazed tile from Malbork Castle: multi-analytical study
Looking at the façade of a historical building, it is often difficult to distinguish between the original decoration and later additions. One such building is the Holy Virgin Mary Church at the Malbork Castle (Northern Poland), built between 1276 and 1406. During the latest restoration works, ceramic tiles with some remnants of the green glaze, decorating the Holy Virgin Mary Church façade, were studied in situ using portable X-ray fluorescence spectrometry. Micro-samples were analyzed in laboratory by scanning electron microscopy with energy dispersive X-ray spectrometry (SEM–EDS) and wavelength-dispersive X-ray spectrometry (SEM–WDS), micro-Raman spectroscopy and powder X-ray micro-diffraction. We found that what was originally thought to be a paint layer was in fact a heavily deteriorated SiO2–PbO glaze. White, yellow and black pigments were found to have been added into the glaze as opacifiers and colorants. Copper and iron were used as glaze colorants. The originally added pigments were transformed into new phases, such as antimony-doped tin oxide. The technology used to produce the glazed tiles was identified. All the results collectively confirmed the medieval origin of the green glazed tiles.Graphical abstractGothic green glazed tile from Malbork Castle: multi-analytical study.
The beginnings of tin-opacification of pottery glazes
A multidisciplinary programme of research on the glazed ceramics of the Islamic world has been focused on questions of their dating, provenance and technology. One particular question has been the development of tin-opacified glazes, and the nature of glaze opacification generally in the Islamic world. The findings of the various studies combine to indicate that tin was first used experimentally in Basra, Iraq, in the first half of the eighth century AD, apparently within the context of pre-Islamic opaque-glaze technology. Over the course of the next century, an opaque-glaze technology entirely reliant on tin oxide inclusions was developed in Iraq and Egypt and, subsequently, this technology spread to the rest of the Islamic world and also to Europe.
Color: Universal Language and Dictionary of Names
The Universal Color Language (UCL) has been revised and will be published together with the 7th printing of the Color Names Dictionary. It serves as the means of updating the Dictionary. The UCL brings together all the well known color-order systems and methods of designating color. It interrelates them in six correlated levels of fineness of color designation, each higher level indicating a finer division of the color solid. It follows closely the original requirements for the ISCC-NBS Method of Designating Colors stated in the Color Names Dictionary. They were: a) accurate enough to satisfy a scientist, b) usable enough to satisfy a manufacturer and c) simple enough to be understood by the average person on the street. The first requirement is satisfied by levels 6 and 5, the second by levels 5, 4, and 3, and the third by levels 3, 2, and 1. The UCL is being increasingly used by science, education, art and industry. Instructions are included for the application of the UCL at each level. -- AATA