A range of scientific techniques is used to investigate heritage materials from archaeological and maritime sites, collections, and historical buildings. The analytical equipment allows to enhance the recording and interpretation of objects including information about the creation, use, modification, and burial of objects, and to inform the in situ preservation of sites and the conservation of artefacts from a maritime context. The laboratory equipment includes: 1.Scanning electron microscope with energy dispersive spectrometer (SEM-EDS, FEI-Inspect F combined with an energy dispersive spectrometer INCA X-Act); 2.Bench-top micro-X-ray Fluorescence spectrometer (micro-XRF, M4 Tornado, Bruker); 3.X-ray diffractometer (XRD, D8 Advance, Bruker); 4.Fourier-transform infrared (FTIR) spectroscopy (Spectrum 100 spectrometer, combined with an Attenuated Total Reflection (ATR) diamond-ZnSe crystal accessory, Perkin Elmer); 5.Freeze-dryer (LyoDry).
Potential Results
SEM-EDS is used for high resolution and high magnification imaging and to carry out quantitative and qualitative analysis of chemical elements in a wide range of materials (glass, metals, ceramics, stone, mortar, paintings, textiles, wood, leather, etc). The micro-XRF spectrometer is optimized for analyses of points, lines and 2D area scans (element mapping) of samples. The X-ray beam is focused with polycapillary lens and the spot size is about 20 µm. The sample chamber size is 600 mm x 350 mm x 260 mm (WxDxH), therefore full objects can be analysed. The vacuum option extends the analytical range to light elements, allowing quantitative analysis of glass, stone, mortars, ceramics and other organic materials like mordants in textiles. For SEM-EDS and micro-XRF, the accuracy and repeatability precision of the results are regularly checked by analysing certified reference materials to carry out quantitative analysis. XRD is used for the identification of crystal phases and minerals in stone, mortars, ceramics, and pigments, and for the characterisation of products of degradation and corrosion on metals, stones, mortars and paintings. Studies by FTIR spectroscopy can be carried out to identify the molecular composition of the artefacts and products of degradation and corrosion, and to study of the kinetic of degradation of materials. It has been applied to study both organic (resin, gums, waxes, binding media, textiles) and inorganic (building materials, glass, metal, pigments) materials, to determine their composition and state of preservation. A small sample/object can be analysed without any pre-treatments using ATR accessory. Small samples can be grinded to a fine powder and mixed with KBr to create KBr pellets to be analysed in transmission mode. The freeze dryer is used for the drying of waterlogged archaeological wood, leather and textile. It is equipped with a modular shelving system, that can be removed to accommodate larger items. A gas inlet allows the chamber to be flooded with other gases and would make it suitable for pest eradication treatments.