Nondestructive, optical and X-ray analytics with high local resolution on attic white-ground lekythoi

Abstract We present new results of analyses regarding not only the chemical and mineralogical composition but also the manufacturing technology of white-ground Attic lekythoi using non-destructive and locally highly resolved X-ray microdiffraction (μ-XRD 2 ), micro -X-ray fluorescence (μ-XRF), an X-ray colour camera and 3-dimensional (3D)-laser scanning microscopy. From these first results of exemplary two lekythoi supposed to be of two different types, it is obvious that different white-ground materials had been used. Only One of the investigated lekythoi showed the well-known white-ground consisting of a fired clayey, probably kaolinitic, slip. Findings on the second lekythos reveal gypsum as a white-ground material, which must have been applied after firing but before further cold painting. Gypsum was probably used as it may have been much cheaper and its application has been technologically simpler compared to a clayey slip applied before firing and was reserved for special types of lekythoi. Astonishingly, an overlaying black painting was identified as the typical Fe-spinel containing pigment, up to now only known as black gloss which is produced during firing of an Fe-containing illitic clay on e.g. red- respectively black-figured Attic pottery. This suggests an independent production process for the black gloss, which allowed a cold application of the pigment on the gypsum white-ground without further firing. Using an X-ray colour camera, for the first time a hidden drawing on this lekythos was detected, probably had been used as a preparatory sketch. On the same sample, an additional extremely fine scoring was found revealed using 3D-laser scanning microscopy, probably in order to sharpen the contours during finishing the painting. This possibly hints to precious objects only for decorative purposes. All these results, obtained using a multi-methodically strategy by state-of-the-art techniques, provide new hints not only regarding the manufacturing technology. Also the classification of the lekythoi, knowledge transfer, trade, utilization and many more may be deduced.