ETAPA DE MANTENCIONETAPA DE CORRECION

After the removal of the Turkish decorations of the dome, a mosaic organized in concentric circles was found. A badly damaged medallion appeared at the centre of the dome, showing what is left of a haloed Christ with his right hand raised, dressed in a tunic, and holding a cross [fig. 29].

55 _{MENTZOS,BARBIN, AND HERRMANN 2002;ILIADIS 2001 and 2005.} 56 _{MENTZOS,BARBIN, AND HERRMANN 2002,324-326.}

The medallion is encircled by a row of stars, a wreath with fruits of all seasons, and a rainbow. In the next zone, four winged angels support the central medallion with their hands. The rayed head of a phoenix stands between two of them on the east side, just below Christ’s head in the central medallion. On the south, four rays are still visible between two of the angels; their source of origin is however unknown.

Unfortunately, this is all that is left of the first mosaic circle of the dome decoration. Indeed, the first and second concentric circles have all but disappeared. Only a few scattered fragments of the second section are visible, just above the lowest frieze, and show a series of feet in sandals walking in a garden-like setting. The second mosaic zone is divided from the lowest frieze by a mosaic cornice representing architectural mouldings. In the lowest friezes, a series of eight panels are separated from each other by bands of acanthus leaves. Unfortunately, the eastern panel is now missing. The panels bear the same broad composition: two or three orantes stand in front of luxurious architectural structures that dominate each of the scenes. The buildings represented are all organized around a central exedra, where different elements are represented. In the north- and south- eastern panels, a bust of Christ being raised by two angels decorates the central pediment [figs. 30-31]. In the northern and southern panels, a jewelled cross surrounded by a stream of water and with a dove descending over top of it stands under a hexagonal canopy [figs. 32-33]. In the north- and south-western panels a throne filled by a closed book is covered by a

circular canopy [figs. 34-35]. Although the mosaic is heavily damaged in the centre of the western panel, an apse enclosed by slabs is still visible [fig. 36]. The background of the entire mosaic is pervaded by gold; the only exceptions are Christ’s medallion, which has a silver background, and the garden-like ground of the second circle where the figures are walking.

Only a few of the vaults of the bays and lunettes bear their original decoration. Mosaics are still visible in the vaults of the south-eastern, southern, and western bays, and in the south-eastern, western, north- western, and north-eastern lunettes. Various geometric decorations cover the lunettes, while geometric patterns are filled with vegetal and animal elements in the mosaic of the bays. Only the southern bay has a richer decoration, where a large cross is depicted on a silver background with caskets of fruits alternating with birds.58

2.1 The mosaic: a survey and technical notes

During a recent survey at the Rotunda, the Ninth Ephorate of Byzantine Antiquities of Thessaloniki, to which I am very grateful, allowed me to walk on the scaffolding around the dome. As a result, I was able to observe the mosaic at a close range and was able to see the present state of work.59 The staff of the Ninth Ephorate provided me with ample technical information and allowed me to observe the mosaic and examine the drawings, but I was not allowed to take new pictures or to make

58 _{For the mosaic of the southern bay, see: TORP 2001, 295-317.} 59 _{The survey took place in June 2006.}

sketches of the details, official copies of which will soon be published by the Ephorate.

When entering the church, one has the impression of a huge, bare building, partially due to the fact that the keystone of the dome stands at a height of 34 m. The lack of the marble and mosaic decoration, which have been mostly destroyed, leaves the extant mosaics alone to convey the impression of the original interior. The golden and colourful mosaics shine against the bare brickwork, appearing extremely radiant. Although the dominant colour seems to be gold, the mosaic decoration enriches the church with a great variety of other bright colours. Where the mosaic is extant, the dome shines as if it was directly reflecting the light. This is due to the mosaic’s technique. The setting of the tesserae, their size (1 cm2), and the skilful play with colour together convey an impression of brightness.

All of the tesserae are made of glass, except for a few colours – the white and a few nuances of red, pink, and purple – for which stone cubes are used. The gems and pearls that cover the encrusted columns and the crosses depicted in the mosaic are in fact large glass tesserae. Although mother-of-pearl was used in addition to glass in the tesserae of the sixth- century mosaics of Ravenna,60 there is an almost constant use of glass

tesserae in the Rotunda mosaic. Although the range of colours is quite

limited, one has the impression that the panel is very colourful due to the

60 _{In the mosaics of St. Apollinare nuovo they were replaced by big buttons during the}

restorations of the last century (information coming from the direct experience of the author).

technique used.61 The combination of differently coloured tesserae produces various nuances: in the peacock’s tail, for instance, the juxtaposition of yellow next to blue and red makes a green colour that is rendered through the reflection of light on the blue, yellow, and red

tesserae. The clever use of differently coloured tesserae to make new

colours is also made possible by their small size. This allowed them to be easily combined, so that it is possible to render details of the buildings, facial traits, and features of the costumes.

Silver and golden tesserae are cleverly and differently used depending on the elements of the mosaic. While the background is made of golden and silver cubes, only gold and radiant colours are utilized for the buildings. In the buildings, the shading is rendered through the interplay of golden and colourful tesserae. The structures that are intended to be portrayed in the light are made of golden tesserae; those that are supposed to be in the shade are done with different nuances of yellow, red, and brown. Although no direct light could possibly reach the dome, when the Rotunda is lit, the golden part shines; when it is in the dark, the other parts shine. The background of the mosaic is always bright due to the mix of silver and golden tesserae.

A striking feature of the overall architectural frieze is the marginal amount of optical distortion. Since dome mosaics and some wall mosaics are intended to be seen from the floor and thus rely on optical rules for

61 _{Information provided by Themi Kakagianni, who guided me during the visit on the}

correctly rendering images seen from afar, the depictions often seem disproportionate when seen close up. Although the frieze was covered by three floors of scaffolding, a fact that only allowed me to analyse one long, round area at a time, the proportions of the human figures and the details of the buildings did not appear to be distorted to me. This could be a false impression, due to the impossibility of viewing the frieze as a whole. However, if this is true, it could be important in defining the mosaic technique as well as perhaps for the determination a specific school of mosaicists.