Materials and methods
Fresco: above the layer of arriccio is a fine plaster (4-5 mm) called intonachino, spread rapidly and unevenly. The fresco took eleven giornate, starting from the horse on the left of the Sun Chariot and continuing to the other side of the painting.
Stuccoes: the preparatory layer is an impasto mostly made up of aerial lime and silicatic sand with some carbonate sand, while the surface impasto is aerial lime, quartzitic-silicatic sand and in some cases, chalk.
Recorded restoration work
There was originally a triumph of hues, with coloured surfaces (azurite backgrounds, reliefs of white lime pigment called bianco di San Giovanni and particles of yellow ochre) set off by the frame of the fresco which was gold-leafed onto a yellow base. These surfaces were later re-painted various times.
In preparation for the Giulio Romano exhibition of 1989, restoration firm Gianfranco Mingardi of Brescia stabilized the paint layer, removed the salt efflorescence and cleaned the painted surfaces.
Following chemical-stratigraphy analysis (by Consulting Scientific Group “Palladio” of Vicenza), restoration involved the vault stuccoes, the fresco and the plaster casts on the walls (Maria Chiara Ceriotti for Consorzio Arkè and Alberto Fontanini for Marchetti & Fontanini).
Conditions prior to restoration
Fresco: There were numerous small areas where the intonachino had become detached and there was a large loss beneath the Moon. The horse to the right of the Moon was badly stained as the brown colour underneath came through where the grey glaze had been lost. Many of the problems were related to earlier restoration, such as the abrasions brought about by strong mechanical cleaning (which caused the a secco finish to be lost), a patch of over-cleaning, and repainting where an oily binding solution had been used on the pink part of the ray and around the face of the Sun, on the drapery and the sky. The flesh tones had yellowed and become stained, probably due to a fixative, to which time had added a general layer of grime.
Stuccoes: The stuccoes had losses on the surface and had turned brown, while the background colour had been scraped, energetically washed and then plastered with lime. There were also the remains of some recent repainting with titanium white, and the gilding on the frame around the fresco had been lost, perhaps scraped off mechanically and repainted in yellow ochre.
Work carried out
Fresco: The fresco was dusted, stabilized and chemically cleaned; the repainting was partially removed.
Stuccoes: After dusting the surfaces and consolidating all the detached parts of the preparatory layers, the old plaster stopping was removed. After the mechanical and chemical cleaning and stopping up the losses, the backgrounds of the lozenges were given a light blue watercolour wash, while the stucco reliefs were lightly plastered with lime and ventilated clay: this restored the original colours to the decoration.
Camera del Sole e della Luna: particolare della decorazione in stucco della volta prima del restauro Arké e Marchetti & Fontanini 2000.
(foto Archivio Museo Civico di Palazzo Te)
Chamber of the Sun and the Moon: detail of the stucco decoration in the vault before the Arké and Marchetti & Fontanini restoration 2000 (photo Archivio Museo Civico di Palazzo Te)
Camera del Sole e della Luna: la volta dopo il restauro Arké e Marchetti & Fontanini 2000.
(foto Paolo Perina per SIRBeC 2007, Centro Studi e Documentazione Collezioni Civiche)
Chamber of the Sun and the Moon: the vault after the Arké and Marchetti & Fontanini restoration 2000 (photo Paolo Perina for SIRBeC 2007, Centro Studi e Documentazione Collezioni Civiche)
P. ARTONI, G. MAROCCHI, I recuperati ambienti di Palazzo Te in Mantova. Tracce per una storia dei restauri, in “Storia e cultura del restauro in Lombardia. Esiti di un biennio di lavoro in archivi storici”, Associazione Giovanni Secco Suardo, Lurano, Il Prato editore, 2009, pp. 141-187.