NMR as a new tool for cultural heritage application: The provenance of ancient white marbles

Abstract

Identifying the origin of marble used in antiquity brings back to light details of the economic, social and political organization of classical societies, and characterizing in depth the chemistry of marble is key to discovering its provenance. Beyond X-ray diffraction, which could reveal the presence of discriminant secondary crystalline phases and the quantification of accessory minerals combined with a multivariate analysis approach, solid-state nuclear magnetic resonance (NMR) enables one to recognize the local structure arrangement of both crystalline and amorphous materials by looking at one or more selected atoms. In present paper targets the 13 C nuclide, and thus the major component of marble, calcium carbonate. Whatever their geological origin, marbles 13 C-NMR spectra present only one resonance corresponding to the carboxyl function whose intensity and line width vary from one marble to another. If the variation of the NMR signal intensity observed is the result of great T1 variations (from 220 to 5300 s) and is linked to iron content, the line width reflects defects in the calcite crystal in which calcium has been replaced by another element such as magnesium, aluminium or strontium. The specific profile of the NMR signal has been used successfully to help determine the origin of some archaeological items.

A New Database of the Quantitative Cathodoluminescence of the Main Quarry Marbles Used in Antiquity

“…Due to its importance in sculpture, the recently discovered Göktepe marble has received much attention from different scholars. Thus, it has been the subject of various publications aiming to discriminate it from other fine-grained marbles [18,20,29,[31][32][33]. The scarce analyzed samples in this contribution have been plotted separately into two subgroups in the CL diagram (Figure 7b), according to who supplied each set of samples.…”

Sourcing Herod the Great's calcite-alabaster bathtubs by a multi-analytic approach

“…The former studies involved minero-petrographic and trace-element analyses, as well as δ 13 C, δ 18 O, δ 87 Sr isotopic measurements for provenance determination. Solid-state 13 C-NMR was also argued to be successful for this analysis, by comparison of the intensities and line-widths of 13 C-NMR profiles 19 .…”

13C, 25Mg, and 43Ca Solid-State NMR for the Purpose of Dolomitic Marbles Provenance Elucidation

“…13 C NMR spectra of all of the samples were recorded with a 9.4 T Avance NMR apparatus from Bruker (Wissembourg, France) equipped with a broad band solid-state CPMAS 4 mm probe containing up to 200 mg of marble powder (CESAMO facilities) using the experimental protocol previously described [ 19 ].…”

“…To the established methods used, such as isotopic and elemental analysis, we add a third technique, solid-state nuclear magnetic resonance (NMR), which allows the deciphering of materials at a molecular level. In preliminary works, 13 C NMR has been successfully developed for determining the provenance of some white calcitic marbles at a region scale [ 19 ] or even at a quarry level [ 20 ]. In the present work, in addition to carbon, two other nuclei—magnesium ( 25 Mg isotope) and calcium ( 43 Ca isotope)—are investigated in order to track differences at the molecular scale between the dolomitic varieties that can be useful for their discrimination.…”