## 1 Introduction  
Macro X-ray fluorescence mapping, widely known as MA-XRF in the scientific community [1], is now one of the most valuable tools aiding the heritage science field. MA-XRF analysis produces elemental distribution maps of a scanned area of an object, proving to be exceptionally useful not only for material characterisation but also for understanding an artist's painting and production techniques. In addition, mapping makes it easier to associate trace elements with a specific colour or area, even in noisy maps, with respect to a \"traditional\" single point measurement. Moreover, as MA-XRF renders not only spectra but also images, it can also be easily adopted by non-X-ray experts, such as conservators or art historians.  
The technique is relatively fast; the acquisition time naturally depends on the dimensions of the area of analysis and the dimensions and characteristics of the instrument employed. Numerous types of equipment are available nowadays, ranging from small and easy-to-transport instruments customized for the analysis of areas of only a few cm\({}^{2}\)[2, 3] to massive scanners allowing large areas to be analysed in a reasonably short acquisition time [4, 5, 6].  
Numerous successful applications of MA-XRF in heritage science have now been described in many papers. Many of these applications involve the analysis of paintings [7, 8, 9, 10],but these applications also range from manuscripts [11; 12], painted papers [13], metals [14], glasses [15], tiles [16], and archaeological sites [17] to furniture [18] and many others.  
The research presented here used the MA-XRF scanner specifically designed and developed for heritage science by INFN-CHNet, the Cultural Heritage Network of the Italian National Institute of Nuclear Physics [19; 20; 21]. There are several partners within this network, one of these being the Opificio delle Pietre Dure (OPD) in Florence, a reputable conservation centre belonging to the Italian Ministry of Cultural Heritage. The Florence division of INFN works in close and fruitful collaboration with OPD, mainly for the analysis of paintings. One of these is the focus of this work, a painting produced by the famous Flemish painter known as [PERSON], who was active in the first half of the XV century. This painting, the _Entomment of Christ_, belongs to the collection of the Uffizi gallery in Florence and was likely painted in 1460. The main aim of this work was to gain further information on the painting palette and techniques used by [PERSON], comparing these results with those from other works by the artist, as specifically described in the results section. The materials analysis also aimed at supporting the ongoing conservation intervention.  
To accomplish this purpose, the INFN-CHNet MA-XRF scanner has been proven to be an invaluable tool for an early non-invasive analysis of the elemental composition of the materials, the most of which could be reasonably hypothesised. Needless to say, MA-XRF alone cannot conclusively identify most of the pigments or other materials and thus cannot ascertain their exact nature. Other analytical methods are indeed routinely employed in combination with a comprehensive material characterisation. It is, however, true that MA-XRF analysis allows for a relatively fast and complete analysis able to provide, at the very least, a first overview or hypothesis of the materials and techniques employed by the artist, as will be demonstrated in this work. These results can be considered a first reliable basis for material identification and may act as an guide for the use of consecutive analytical methods.