Table 5: Examination and analytical techniques used in the study of bronze sculpture, sorted by process steps

Table 5
Table 5
Examination and analytical techniques used in the study of bronze sculpture, sorted by process steps
Refer to tables 10 and 13 and the relevant chapters in volume II for the signification of acronyms, and advantages and limitations of each examination and analytical technique. For each process step, there are numerous risks of misidentification/misinterpretation, so refer to the relevant chapters for more details.
PROCESS STEPS METHODS OF EXAMINATION(1) METHODS OF ANALYSIS(2) PROVIDE INFORMATION ON: SEE
Usual techniques and tools Rarer techniques(3) Usual techniques and tools Rarer techniques(4)
Casting processes Naked-eye examination (good lighting at different angles, including raking light and RTI), portable loupe, stereo microscope, magnet, borescope or endoscope, X-radiography 3D scanning/photogrammetry, high energy X-rays (1 MeV and beyond) or gamma or neutron radiography, computerized tomography (CT), ultrasonic testing, thermography - Carbon-14 dating (of iron armatures) Method of fabrication of the models, degree of modeling, type of cast (hollow, solid, direct, indirect, other), casting method, possible absolute and relative dating I.1
II.8
Core Naked-eye examination, borescope or endoscope, stereo microscope, X-radiography High-energy X-rays (1 MeV and beyond) or gamma or neutron radiography, computerized tomography (CT)
  • Petrographic analysis (PLM)
  • Microchemical tests, XRD, XRF, SEM
  • Cathodoluminescence microscopy
  • Elemental analysis: LIBS, PIXE, PIGE, EPMA, AAS, ICP-AES, (LA-)ICP-MS, NAA
  • Luminescence and carbon-14 dating
Identification of core materials, method of fabrication, provenance of core materials, possible absolute and relative dating II.7
II.8
Metals(5) Naked-eye examination, olfactory testing -
  • Elemental analysis without sampling (XRF)
  • Elemental analysis with sampling (microchemical tests, XRF, SEM-EDS)
  • Elemental analysis without sampling (LIBS, PIXE, PIGE, LA-ICP-MS)
  • Elemental analysis with sampling (EPMA, NAA, AAS, ICP-AES, ICP-MS)
  • Metallography
  • Testing of physical and chemical properties
Identification of the alloy, characterization of its properties, provenance of raw materials, possible relative dating I.2
II.5
Casting defects Naked-eye examination (good lighting at different angles, including raking light and RTI), portable loupe, stereo microscope, borescope or endoscope, X-radiography 3D scanning/photogrammetry, RTI, high-energy X-rays (1 MeV and beyond) or gamma or neutron radiography, computerized tomography (CT), ultrasonic testing, thermography, eddy currents, image analysis - - Quantity, form, distribution and location of defects, causes of flaws I.3
fig. 150 (defects diagram)
Repairs Naked-eye examination (good lighting at different angles, including raking light and RTI, and UV light for nonmetallic fills), portable loupe, stereo microscope, borescope or endoscope, X-radiography 3D scanning/photogrammetry, RTI, high-energy X-rays (1 MeV and beyond) or gamma or neutron radiography, computerized tomography (CT), ultrasonic testing, thermography, eddy currents, image analysis
  • Elemental analysis without sampling (microchemical tests, XRF)
  • Elemental analysis with sampling (XRF, SEM-EDS)
  • Elemental analysis without sampling (LIBS, PIXE, PIGE, LA-ICP-MS)
  • Elemental analysis with sampling (EPMA, AAS, ICP-AES, ICP-MS)
  • Structural analysis without sampling (for nonmetallic fills) (XRD, FTIR)
  • Structural analysis with sampling (for nonmetallic fills) (GC-MS, FTIR, Raman)
  • Metallography
Techniques and materials used for repairing, skills of the founder, history of the piece (later repairs), possible relative attribution/dating I.4
fig. 167 (repairs diagram)
Assemblies Naked-eye examination (good lighting at different angles, including raking light and RTI), portable loupe, stereo microscope, borescope or endoscope, X-radiography High-energy X-rays (1 MeV and beyond) or gamma or neutron radiography, computerized tomography (CT), ultrasonic testing, thermography, eddy currents
  • Elemental analysis without sampling (microchemical tests, XRF)
  • Elemental analysis with sampling (XRF, SEM-EDS)
  • Elemental analysis without sampling (LIBS, PIXE, PIGE, LA-ICP-MS)
  • Elemental analysis with sampling (EPMA, AAS, ICP-AES, ICP-MS)
  • Metallography
, assembly techniques and materials, possible relative dating I.5
fig. 201 (assemblies diagram)
Tool marks Naked-eye examination (good lighting at different angles, including raking light and RTI), portable loupe, stereo microscope, borescope or endoscope (for inside marks), X-radiography Silicone rubber impression, 3D scanning/photogrammetry, RTI, high-energy X-rays (1 MeV and beyond) or gamma or neutron radiography, computerized tomography (CT), digital microscopy, rugisometry/tribology techniques (interferometric microscopy, profilometry), microhardness, neutron diffraction - - Degree and type of cold working/working on the model, recurrence of tool marks, artist’s involvement in the process, history of piece (original appearance, later interventions, present condition) I.6
fig. 233 (flow chart)
Gilding and plating Naked-eye examination (good lighting at different angles, including raking light), borescope or endoscope (for drips of gilding on interior), portable loupe, stereo microscope, X-radiography High-energy X-rays (1 MeV and beyond) or gamma or neutron radiography, computerized tomography (CT)
  • Elemental analysis without sampling (microchemical tests, XRF)
  • Elemental analysis with sampling (XRF, SEM-EDS)
  • Elemental analysis without sampling (LIBS, PIXE, PIGE, RBS, LA-ICP-MS)
  • Elemental analysis with sampling (EPMA, AAS, ICP-AES, ICP-MS)
  • Depth chemical profiling (LA-ICP-MS, RBS)(6)
  • Metallography
Techniques and materials, including thickness of plating, history of piece (original appearance, later surface treatment, present condition) I.7
II.6
fig. 304 (flow chart)
Patina Naked-eye examination (good lighting at different angles, including raking light and RTI, and UV light), portable loupe, borescope or endoscope (for corrosion on interior), stereo microscope -
  • UV light
  • Elemental analysis without sampling (microchemical tests, XRF)
  • Elemental analysis with sampling (XRF, SEM-EDS)
  • Elemental analysis without sampling (LIBS, PIXE, PIGE, RBS, LA-ICP-MS)
  • Elemental analysis with sampling (EPMA, AAS, ICP-AES, ICP-MS)
  • Depth chemical profiling (LA-ICP-MS, RBS, NRA, SIMS, Auger spectroscopy, GDL)
  • Structural analysis without sampling (XRD, FTIR)
  • Structural analysis with sampling (GC-MS, FTIR, Raman)
  • Metallography
  • Color measurement
Techniques and materials, including thickness and layering of patina, history of piece (original appearance, later surface treatment, present condition), possible relative dating I.8
II.6
figs. 305, 307, 338 (patina diagram and flow charts)
Inlays and overlays Naked-eye examination (good lighting at different angles, including raking light and RTI and UV light), portable loupe, stereo microscope, X-radiography 3D scanning, RTI, high-energy X-rays (1 MeV and beyond) or gamma or neutron radiography, computerized tomography (CT)
  • UV light
  • Elemental analysis without sampling (microchemical tests, XRF)
  • Elemental analysis with sampling (XRF, SEM-EDS)
  • Elemental analysis without sampling (LIBS, PIXE, PIGE, RBS, LA-ICP-MS)
  • Elemental analysis with sampling (EPMA, AAS, ICP-AES, ICP-MS)
  • Structural analysis without sampling (XRD, FTIR)
  • Structural analysis with sampling (GC-MS, FTIR, Raman)
  • Metallography
History of piece (original appearance, later surface treatment, present condition) I.9
fig. 340 (inlays diagram)
1
For more details on examination techniques, see II.1, II.2, II.3.
2
For more details on analytical techniques, see II.5, II.6.
3
More details in , 54, 57; ,111; .
4
By “rarer” techniques, we mean techniques less available in most laboratories devoted to cultural heritage. Note that this may vary from country to country.
5
This includes repairs.
6
Techniques such as Secondary Ions Mass Spectrometry (SIMS), Auger spectroscopy, and glow discharge ICP are not mentioned here since they are devoted exclusively to modern materials science (thin films in electronics, notably).