TY - GEN A1 - Steger, Simon T1 - Non-invasive, spectroscopic study of a modern reverse glass painting N2 - We present the first spectroscopic study on a reverse glass painting form the classic modern period (1905-1955). Marianne Uhlenhuth’s painting “Ohne Titel, 1954” shows characteristics like experimental use of colorants and abstract compositions, which are well-established in classic modern art. Compared to stained glass, reverse glass paintings are viewed in reflected light, hence they reveal strong and intense colors. New inorganic pigments, development of synthetic organic pigments and the simultaneous supersession of well-known ancient colorants result in experimental works and remarkable pigment mixtures in this period of time. An in-situ, non-invasive approach was used to study the pigments and binding media. In-situ measurements were carried out using Raman spectroscopy (i-Raman®Plus, Bwtek Inc., 785 nm, 20× objective, resolution 4 cm-1), X-ray fluorescence (Tracer III-SD, Bruker AXS Microanalysis GmbH, 40 kV, 15 μA), VIS spectroscopy (SPM 100, Gretag-Imaging AG) and DRIFTS: Diffuse Reflection-Infrared-Fourier-Transform Spectroscopy (ExoScan, Agilent GmbH, 4000-650 cm-1, 256 scans, resolution 4cm-1). The pigments consist of inorganic as well as organic materials. Phthalocyanin green (PG7, colour index No. 74260), viridian and emerald green were used for the green areas. The yellow parts consist of chrome yellow and cadmium yellow. Pigment Yellow 1 (C.I. 11680) was used for the dark yellow/orange part. Red areas were characterized by the presence of cadmium and selenium (cadmium red) in the XRF spectrum. Ultramarine was detected in the blue parts. Concerning the violet color PR81 (bluish red, C.I. 45160:1) in mixture with PG7 (bluish green) were identified as main components. We want to outline that PR81 was rarely found in paintings. It was only recorded in the palettes of Lucio Fontana and Mary Cassatt before. The dark violet areas consist of Prussian blue and an unknown red (organic) colorant. Brown iron oxide was identified as the brown pigment. Bone black in mixture with black iron oxide were used as black materials and zinc white and titanium white as white pigments. XRF analysis of the metal color yields intense copper, zinc and nickel peaks (intensity ratio 3:3:1), which corresponds to “new silver” alloy. Barite and chalk are the fillers in this painting. Results of DRIFTS spectra show gum sometimes mixed with protein or oil (metal soaps) as binding media. The results point out that reverse glass paintings from the classic modern period are excellent examples to study the evolution of new pigments and their acceptance in artist’s palettes. T2 - CSI-XL CY - Pisa, Italy DA - 11.06.2017 KW - Pigments KW - Reverse glass painting KW - Spectroscopy PY - 2017 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/42336 AN - OPUS4-42336 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany