Characterization of Brown–Black and Blue Pigments in Glazed Pottery Fragments from Castel Fiorentino (Foggia, Italy) by Raman Microscopy, X‐Ray Powder Diffractometry and X‐Ray Photoelectron Spectroscopy

Lapis lazuli usage for blue decoration of polychrome painted glazed pottery: a recurrent technology during the Middle Ages in Apulia (Southern Italy)

“…Examination of some fragments from excavations in the abandoned Medieval village of Castel Fiorentino [4,6,10,11,19,20] using Raman microscopy has shown the presence of lapis lazuli in the blue coloration of the background. It is also present in a bowl discovered in the excavations of the SwabianeAngevin fortress in Lucera [6,20], and in the only surviving mosaic tile, extracted from a cut floor tile, belonging to the original mosaic decoration of Castel del Monte [5] (Fig.…”

“…The archaeological and archaeometric research into Medieval ceramics in Apulia identified a new source of the blue colouring used in ceramics covered with a tin based glaze [4,6,10,11,19,20]. Examination of some fragments from excavations in the abandoned Medieval village of Castel Fiorentino [4,6,10,11,19,20] using Raman microscopy has shown the presence of lapis lazuli in the blue coloration of the background.…”

Raman microscopy in archaeological science

“…Similar work on fragments of an unusual blue and black glazed, low quality medieval ceramic from the same area showed that the blue background was afforded by lapis lazuli (lazurite, Na 8 [Al 6 Si 6 O 24 ]S n ÿ ) and not a cobalt-based pigment as suspected [32,34]. However, the black pigment, found by XRD to be MnO 2 , could not be positively identified by Raman microscopy at that time.…”

“…This problem has been ascribed to either defocusing of the laser excitation upon passing through the glassy material [32,34], which itself can act as a lens, or to intense fluorescence generated by organics that have permeated into the porous glaze surface after years of burial [37,101]. A recent FTRaman analysis of blue pigment particles performed through the glaze on pantiles from Bottesford, England has successfully identified azurite as the colourant [16].…”

Micro‐Raman and portable Raman spectroscopic investigation of blue pigments in selected Delft plates (17–20th Century)

“…It is not possible to obtain Raman information on materials through an amorphous glaze that covers the surface without using Raman microscopic profiling to focus through the glaze. [4,5] Using this technique of Raman microscopic profiling, detailed Raman spectra can be obtained of the materials beneath the glaze, of decorations such as the pigment and also of other materials on the ceramic. This is ideal for working with intact pieces of interest to art and archaeology such as porcelain dishes and other ceramics covered in a glaze.…”