On the Two Working Palettes of Almada Negreiros at DN Building in Lisbon (1939–1940): First Analytical Approach and Insight on the Use of Cd Based Pigments

Abstract

This paper reports the first analytical approach carried out on two working palettes by Portuguese modernist master Almada Negreiros, found in 1991 behind old wood cabinets at the DN building in Lisbon. This is the only known occasion Almada left behind the color experiments done before starting to paint in the nearby walls and as such, it is a unique opportunity to analyze the materials and painting techniques that were originally used. The analytical setup comprised in loco technical photography in Vis, UVF and NIR; p-OM, spectrophotometry in Vis and h-EDXRF, complemented by OM-Vis, µ-FT-IR and VP-SEM-EDS of painting micro-samples and pigments in powder form. Preliminary results suggested the use of fresco painting technique and revealed some technical details, such as the use of a coarse lime sand finishing mortar mixed with natural vegetable fibers, and the extensive use of cadmium-based pigments that were not commonly used (or even recommended) in an alkaline environment. The Cd pigments were used alone or in mixtures with Fe based pigments in the warm hues and with cobalt and ultramarine blue pigments in some green paint layers. No clear evidence of organic materials that could have been used as binders was detected.

A Multiwavelength Approach for the Study of Contemporary Painting Materials by Means of Fluorescence Imaging Techniques: An Integration to Spectroscopic Methods

“…Among inorganic pigments used in contemporary art, cadmium yellow, orange, and red ones have a relevant role. They are cadmium sulphides or sulphoselenides and their NIR luminescence has been documented, both with UV and visible excitation [6,16,26,36,37] This property can be observed for cadmium yellow PY35 and cadmium red PR108 in the VIVF image with excitation band at 530 nm (Figure 10b) but is even more evident in the image obtained with 440 nm illumination and filtering above 850 nm (Figure 10c). minded above, the effect of self-absorption by the pigment must also be taken into account.…”

Understanding the chemical and mineralogical composition of commercial henna and jagua tattoos and dyes—a multi-analytical approach

“…High iron and manganese contents may also explain the greenish, brown, and black hues of the henna powders and samples HT-11, HT-16, and JT-4. In fact, natural earth pigments containing iron oxides and/or hydroxides or iron-rich clays can have a wide range of shades from deep purple and brown to red, yellow, and olive green [ 21 ], while manganese oxides are generally linked to brown colors [ 22 ].…”

Traditional and modern pigments in Gino Severini's Swiss murals

“…37,38 Zinc white and cadmium-based pigments, instead, were synthetized later and are rarely found in mid-20 th century murals. 16,39,40 Therefore, in this context, Severini can be considered a pioneer of their introduction in modern mural art. This study shows that the Italian artist adopted specific painting techniques to apply these pigments on the wall.…”

“…In the Swiss murals examined, all the yellow pigments used for the haloes showed an intense orange UVinduced visible luminescence (UVL) that in combination with the visible-induced infrared luminescence (VIL) suggested the presence of cadmium-based pigments. [12][13][14][15][16] In Figure 1, an example of these optical properties is visible in the UVL and VIL images (Figure 1C,D) of the Christ's halo of the lunette mural in the Sion church. The UV response of the yellow paints was explored also at the micron-scale with digital microscopy (Figure 1E-G).…”