Altar of the Swans (inv. no. FAN.1992.371)

Description: The altar has been found in the Roman Theatre of Arles, probably located in the orchestra. It is part of an organic group, together with other two altars, that of Apollo and that of the Civic Crown (see the specific forms).

On the main face two swans hold in their beaks a laurel wreath bound by sacrificial strips. The wings of the beasts are spread out on the three sides of the altar.
On the back face is depicted a wreath of fruits hanging from two palm trees.

Swans and palm trees are part of the iconography associated with the Delian Apollo.

Analytical methods: VIS; UV; MO VIS; MO UV; MAXRF
Autoptic examination: Only a few traces, limited to palm trees, are visible to the naked eye.
Imaging: The imaging has not revealed any fluorescence while microscopy has allowed to highlight the presence of microtraces of colour placed directly on the marble.; FAN.1992_371_fig1
Chemical analysis: The MA-XRF analysis has confirmed the presence of mercury, lead and iron in three areas.
While mercury may suggest the use of vermilion for red, lead might refer to an invisible underlying layer.
The use of a mixture of the three elements has been proposed, however, the homogeneous aspect of the pictorial layer seems to rule out this hypothesis.

Under painting traces: no
Pigments: Vermilion, ochres (orange, yellow, red).
Binder: n.d.
Stratigraphy: Preparatory layer of lead white.
Shading: no
Metallic traces: no
Tools marks: no
Background colour: Red (vermilion).
Apparent marble parts: no
Restorations: no
Polychromy technique: The background retains traces of yellow color from which stand out the colorful patterns.
The flowers, palm trees and base of the altar are characterized by a yellow-brown color, applied directly on the marble. The three elements show different shades of yellow. The flowers and palms are highlighted with red and brown tones.

The eyes and beaks of swans are coloured in orange while the bodies are grey. The wreath shows traces of a warm brown pigment contrasting with the bright tones of pink sacrificial strips and orange beaks of birds.
A ribbon has a very bright color characterized by yellow and red tones.

On the back there is a similar palette: pink strips, red ribbons, fruit wreath with brown-red and yellow tones.

Highlighting motifs: Chromatic correspondence with the decorative apparatus of the altar display context and symbolic use of color.
Polychromy type: The libation tools (strips) and offerings (wreaths) are highlighted by the color that brings them closer to their material reality.

The chosen palette, with the prevalence of red and yellow colors, is closely connected to the complex decorative apparatus of the theater, made of precious colored marbles. The Altar of the Swans is well placed in this context of exhibition, together with the other two altars, that of Apollo and that of the Civic Crown (see the specific forms), which are part of an organic group.
Immagini Tipologia della policromia: FAN.1992_371_fig.3

Bibliography: Neri, E, de Larquier, N, & Strivay, D 2024, 'Colorer et entretenir la couleur : analyse du décor sculpté des autels du théâtre d’Arles', in E Neri (eds), Polychroma. The Meaning of Colours in Roman Sculptures, Silvana Editoriale, Cinisello Balsamo, pp. 226-239.