Application of a Portable XRF Spectrometer for <i>In-Situ</i>and Nondestructive Investigation of Pigments in Two 15th Century Icons

A simple portable X-Ray Fluorescence (XRF) spectrometer was successfully used for in-situ and nondestructive identification of the painting materials in two 15th century icons from the Onufri Museum in Beart, Albania. The spectrometer is based on a low power X-ray tube, a thermoelectrically cooled Si PIN detector and the spectrum acquisition system. It was assembled and adjusted at our laboratory for the investigation of the icons. A small number of pigments were clearly identified by X-Ray Fluorescence (XRF) measurements in both icons. This includes Lead white for the white color, gold and yellow ochre for the yellow color, red lead, cinnabar and red ochre for the red color, as well as cooper based pigments for the green color. At the same time, the investigation raised some new questions that need further investigations by the use of additional analytical techniques. The results show that in both icons are used similar pigments, which are in accordance with the Byzantine icon painting tradition.

Micro-XRF Investigation of Decoration Materials and Painting Techniques in Three 18th-19th Century Mosques in Berat, Albania

We will present here the data obtained from the examination with micro-XRF of a series of micro samples taken from the decorations of three mosques in Berat, Albania. These are parts of an Islamic religious complex situated at the central area of the old town and include the “Helvetia Tekke”, the King’s Mosque and the Bachelors’ Mosque, which were built or reconstructed during the second half of the 18th century and the beginning of the 19th century. Beside the architectural values of the buildings, the interiors of the monuments are decorated with paintings of the walls and the ceilings made of carved wood. The results of the measurements indicate that the preparation layer of the paintings on wooden ceilings was made of gypsum while that of the wall paintings was made of calcium carbonate. The palette includes the following inorganic pigments: lead white, gold, yellow and red ochre, vermilion, red lead, a copper based green, smalt and probably carbon black at Helvetia Tekke;green earth, yellow ochre, red ochre, red lead and cinnabar at Bachelors’ Mosque and red lead, orpiment and Indigo should have used for the original decorations of the ceilings in King Mosque, which are later overpainted with traditional pigments like yellow and red ochre, prussian blue and other modern pigments. Organic pigments, probably indigo and carbon black should have been used for the blue and black color. Similarities and differences observed between the monuments and indications about the painting technique as well as the degradation of some pigments will also be discussed.

Luminescence and energy transfer between Ce^(3+) and Mn^(2+) in alkaline earth borates

The luminescence of Ce and Ce , Mn + co-doped BaB8O13 and SrB4O7 prepared in air is studied. The results show that tetravalent cerium ion can be reduced to trivalent state in the hosts and gives rise to efficient luminescence. Energy transfer between Ce3+ and Mn2+ is possible. Mn2+ ions can be efficiently sensitized by Ce 3+ and exhibit green and red emissions which implied that Mn2 + occupied the crystallographic sites of cations and boron sites of the anoins, respectively. The intensity ratio of red to green emission in matrix increases with the increasing of manganese concentration.