The peace side of the Standard shows how the city, and in particular the ruler, draws upon the agricultural and natural resources of its territory. Agricultural success was necessary to the growth of a city-state and to the benefits it brought to the people. It was also on this success that the ruling group could build a courtly lifestyle involving feasting and entertainment. Agricultural surplus could be used to trade exotic foreign goods, such as the materials used to decorate the Standard, which came hundreds or thousands of miles from the Persian Gulf (the white shells), Afghanistan (the blue lapis lazuli) and India (the red stones).
The Lapis Lazuli Portrait scaricare film
The Ishtar Gate (today in the Pergamon Museum in Berlin) was the most elaborate of the inner city gates constructed in Babylon in antiquity. The whole gate was covered in lapis lazuli glazed bricks which would have rendered the façade with a jewel-like shine. Alternating rows of lion and cattle march in a relief procession across the gleaming blue surface of the gate.
A combined chemical and visual characterization of the pigments was performed by MA-XRF, which resulted in the elemental distribution map of the painting. The main elements identified in each pigment can be used to map the white (Pb), the red (Hg), and the brown (Fe) color, as showed in Figure 6. However, due to the instrumental set-up, light elements as Na, Al, Si, and S that are present in the lapis lazuli could not be detected and, thus, this pigment was not mapped. In addition to the signals of the main pigments components, it is interesting to look at the Cu signal coming from the metal support, that can provide insights about both the thickness and the characteristics of the superposing pigments. In fact, the decrease of Cu signal corresponds to those areas where Pb is present and the higher is the Pb signal the lower is the Cu one. This is explained by the fact that Pb has shielding properties toward X-rays and therefore, the higher are its concentration and thickness the higher will be its shielding effect. In general terms, the use of this technique is comparable to EDS, giving the same analytical results, made exception for the lighter elements detection. However, EDS analyses cannot be performed on large objects, due to the limited analytical chamber dimensions. Furthermore, most of the time it is mandatory to perform in-situ measurements, making XRF the best techniques for such situations. Moreover, this technique combines the advantages of a single spot chemical analyses, as EDS or classic XRF, with the more straightforward visual interpretation given by imaging techniques as UV, IR, and IRFC. If needed, the use of this technique would allow to detect hidden paintings below the outermost surface, due to the difference in composition between pigments used in different time of history (Saverwyns et al., 2018). Therefore, even if time consuming, the application of MA-XRF for the study of this kind of artifact allows to have many information by a non-invasive approach and to have an easier discussion of the results between scientist and conservators or art-historians. 2ff7e9595c
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