An inductively coupled plasma study and an ion cyclotron resonance matrix‐assisted laser/desorption study at high mass resolution of two ancient Maya greenstone artifacts from Pacbitun, Belize, and two decorative jade specimens
Rapid communications in mass spectrometry, 2020-09, Vol.34 (S4), p.e8629-n/a
Two Early Classic period (ca 250–600 CE) Maya carved, greenstone jade pendants, Specimens A and B, were recovered from the Pacbitun site in Belize in 1987. Mass scans of resolution ~600,000 were obtained for the jade pendants and two British Columbia jade ornaments.
Polyatomic ions from jade grit have been observed using Fourier transform ion cyclotron resonance mass spectrometry (FTICR‐MS), specifically the Bruker Daltonics, SolariX XR, combined with matrix‐assisted laser desorption/ionization (MALDI); the matrix material was α‐cyano‐4‐hydroxycinnamicacid.
Presented here is an interpretation of the mass spectrometric observations from multiplicities of silicate materials. Observation of novel polyatomic ion species of m/z 800–1400 indicate the ejection of charged ensembles composed of 60–180 atoms from jade grit. The charged ensembles represent minute regions of jade grit that have retained many of the spatial relationships of atoms within the jade; the required ejection energy is provided by laser photons accumulated in the matrix. Acid solutions of grit from Specimens A and ornament KMM were analyzed by inductively‐coupled plasma mass spectrometry. The novelty of this application of mass spectrometry to jade was reported in the Journal of Archaeological Science: Reports.
Isotopic fine structure analysis can yield elemental compositions for ions composed of base isotopes together with stable isotope intensities arising from ions with one and two additional neutrons. The analysis is challenging as jade is a multiplicity of similar solid solutions; thus, a multiple isotopic fine structure approach has been explored. Attempts to compose ensembles of atoms, of those elements found normally in coloured silicates, to match the observed ion mass/charge ratios were unsuccessful without the addition of multiple hydrogen atoms. The production of polyatomic ions of siliceous material may permit impinging fine glass coatings onto construction materials for protection against fire and weather.