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Fourier Infrared Spectroscopy (FTIR) X-ray Diffraction (XRD) X-ray Fluorescence Spectroscopy (XRF) Raman Spectroscopy Scanning Electron Microscopy with Energy-dispersive X-ray Analysis (SEM-EDS) Reflectance Transformation Imaging (RTI) Infrared Imaging Digital Radiography Sample size needed 0.2-1 sq. mm 0.1 to 1 sq. mm 0.1 to 1 sq. mm Microscopic up to a few inches Microscopic up to a few inches Whole objects Whole object Whole object Can identify Many organic and some inorganic materials Inorganic and organic crystalline compounds Inorganic elemental composition Many organic materials and minerals Inorganic elemental composition Can enhance visibility of subtle textures, features, and inscriptions Can reveal underdrawings, enhance faded/obscured text, and differentiate materials Internal structure, condition, and materials Suggested for Plastics Paint binding media Some pigments & fillers Varnishes and coatings Some efflorescence Pigments Corrosion products Metals Minerals Some fillers Pigments Fillers Corrosion products Metals Ceramic glazes Presence/absence of heavy metals Plastics Fillers Corrosion products Pigments Pigments Fillers Corrosion products Metals Ceramic glazes Presence/absence of heavy metals Inscriptions, tool marks, subtle textures, and variation In surfaces Underdrawings Signatures/inscriptions Faded writing Paintings Sculptures Metals Wood Ceramics Art and Science of Smithsonian Collections: What Technical Study Can Reveal About Objects Identifying Modern Materials: Duane Hansen’s Woman Eating, 1971, Smithsonian American Art Museum Reading Hieroglyphics: Rongorongo Board, Easter Island, ca. 1886, National Museum of Natural History Identifying Mineral Content: Chinese Jade Collections at the Freer Gallery of Art ǀ Arthur M. Sackler Gallery Sample # Description Material Identification 1 Adhesive from interior of shopping bag Polyisoprene / natural rubber 2 Substrate of sculpture (unpainted area below PR leg) Talc, phthalates in polyester resin 3 Paint medium (upper thigh of PR leg) Alkyd, talc, calcite (possibly zinc oxide and titanium dioxide) 4 Synthetic hair from wig Poly(acrylonitrile-co-vinyl chloride) coating with wax 5 Fiber from dress Cellulose/Cotton, talc 6 Ice cream paint medium Acrylic emulsion, calcium sulfate dihydrate 7 Residue from table top Sugar 8 Plastic button from dress Polyvinyl acetate, phthalate 9 Ice cream substrate Plaster, additives 10 Adhesive from PL arm Triterpenoid resin Summary of materials identified by FTIR from Duane Hansen’s Woman Eating. p-XRF spectrum of watch bracelet: Ni, Fe, Cr, (Au) Data suggest: nickel-chromium-iron alloy with traces of gold p-XRF spectrum of chocolate ice cream: Fe, Se, Sr, Cd, Ba, Zn, Ca Data suggest: iron oxide (Fe 2 O 3 ), barium sulfate (BaSO 4 ), cadmium red (cadmium sulfide CdS + cadmium selenide CdSe ), possibly small amounts of zinc oxide (ZnO) or zinc containing metal soaps FTIR spectrum (left) and Vis/NIR spectrum (right) of a jade Bi disk (F1912.40). Absorbance (a.u.) Wavenumber(cm -1 ) Wavelength(nm) Reflectance Wavenumber(cm -1 ) Absorbance (a.u.) FTIR spectrum (left) and Vis/NIR spectrum (right) of a bead from the Shang dynasty (S1987.935.14). Imaging and analytical techniques available at the Museum Conservation Institute (MCI) Defining Degradation: Zinc Lithographic Plates from The Chicago Defender, 1920s, National Museum of African American History and Culture μ-XRF spectra: Flat blue region (blue), etched pit regions (orange), and white corrosion products (green) 3D digital microscope image of surface area in good condition 3D digital microscope image of heavily corroded area on the surface Goal: To understand the sculpture’s materials prior to cleaning and other conservation and preservation treatments. The sculpture was conserved in the museum galleries in Fall 2015 with support from the Smithsonian Women’s Committee. Analytical method: Fourier transform infrared spectroscopy (FTIR) and portable X-ray fluorescence (p-XRF) Goal: To understand the materials of the zinc plates as well as their condition and corrosion before conservation treatment for a planned exhibition. These plates allowed accurate black-and-white photographic reproductions in The Chicago Defender, a historically important newspaper for African-American readers. Imaging and analytical methods: Micro X-ray fluorescence (μ-XRF), 3D digital microscopy (X-ray diffraction, scanning electron microscopy) Goal: To determine mineral composition of Chinese jades to help develop a scholarly understanding of jade and stone materials of the FǀS holdings. This work will be incorporated into a digital catalogue being organized by FǀS Ancient Chinese Art Curator Keith Wilson which will be available to scholars, collectors, and the general pubic. Analytical methods: Portable Fourier transform infrared spectrometry (p-FTIR) and Visible/Near infrared spectrometry (Vis/NIR) Identification: Quartz, SiO 2 Identification: Nephrite, Ca 2 (Mg, Fe) 5 Si 8 O 22 (OH) 2 Eloise Shearer p-XRF spectrum of flesh on PL leg: Zn, Ti, Ba, Fe, Pb, Sr, Ca, Mn Data suggest: zinc oxide, barium sulfate, titanium dioxide, iron oxide/earth pigments, red lead ATR-FTIR spectrum of fiber from dress: Woman Eating’s fiber from dress (red), cotton fabric (light blue), talc (green). 5 10 15 20 25 - keV - 0 2 4 6 x 1E3 Pulses Fe Se Sr Cd d Ba Zn Ca Rh 4 6 8 10 12 14 - keV - 0 20 40 60 80 100 120 x 1E3 Pulses Fe Ni Cr Au 5 10 15 - keV - 0 5 10 15 20 25 x 1E3 Pulses Zn Ba Ti Mn Fe Pb Sr Ca 2 4 6 8 10 12 - keV - 0 200 400 600 800 Pulses K Cr Fe e Zn Zn Pb Pb Al S Cl Ca 465 666 1013 1162 1315 1429 1723 2851 2902 3325 3674 Talc Mg3Si4O10(OH)2 Cotton fabric, unbleached standard 2005.22a-z_s5_fiber dress_ATR_a -0.09 -0.08 -0.07 -0.06 -0.05 -0.04 -0.03 -0.02 -0.01 -0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 Absorbance 500 1000 1500 2000 2500 3000 3500 Wavenumbers (cm-1) RTI Specular Enhancement View Goal: To enhance the visibility of carved hieroglyphics on the board to aid in the translation of the inscriptions. This project is part of a larger collaboration with NMNH Anthropologist and Curator of Oceanic Ethnology Adrienne Kaeppler. Imaging technique: Reflectance Transformation Imaging (RTI) Board side A Board side B Default View NMNH A129774 Reflectance
