|Address:||Hradčanské náměstí 5, Praha|
|Description of work:||Restoration of the sculpture “Musica” |
Restoration of stone coats of arms on the façade
|Investor:||Ministry of Foreign Affairs of the Czech Republic|
|Contractor:||GEMA ART GROUP a.s.|
|Implementation:||09/2002 – 04/2003|
A group of burghers’ houses, whose existence is documented in written sources dating to the 1350s, originally stood on the site of today’s Tuscan Palace. The settlement had been in the ownership of Count Lobkowicz since the 1650s and was sold by him to Count Michael Oswald von Thun in 1685. Count Thun was one of the most influential people of this time: as a member of the Secret Council and Governor and Associate Judge of the Provincial Court of Justice in the Czech Lands he required an aristocratic establishment commensurate with his importance.
The design of the palace was the work of the French architect and artist Jean Baptiste Mathey. It had the form of four three-storey wings built around an enclosed courtyard. The most intricate and ornamented surface was that of the exterior façade of the main entrance, which led to an anteroom with a fireplace and the main hall. The hall was the only part of the building not completed during Count Thun’s lifetime. The façade was ornamented with stone bas-reliefs of the family Thun–Hohenstein coats of arms. Italian architect Giacomo Antonio Canevalle took part in the construction of the palace alongside Jean Baptiste Mathey. He was responsible for the two pavilions built into the main entrance, elevated above the roof level and connected by a roof terrace. It is this architectonic feature which gives the palace its Italianate appearance. Statues depicting allegories of the Seven Liberal Arts, the work of Jan Brokoff, were placed on the attic of the palace.
A further spell of building activity occurred after 1718 when the palace was bought by the Countess Anna Marie Frances of Tuscany. During her ownership the main hall, richly decorated with bands of wall paintings and medallions of painted busts, was completed and additional building alterations under the leadership of the Czech architect Václav Špaček were undertaken. The original coats of arms on the façade were replaced by more extravagant ones of the Saxe-Lauenburg family, from which the countess was descended.
After her death in 1741 the Tuscan Palace deteriorated and lost its privileged position as a prime aristocratic stately home; from then onwards it was used only for administrative purposes. During the reign of the Emperor Ferdinand V (1835-1848) the palace became the property of the Hapsburgs, who owned it until the establishment of an independent Czechoslovak Republic in 1918. From this year the palace premises had traditionally been the seat of the Ministry of Foreign Affairs.
Two significant building alterations took place during the 20th century. Between 1941 and 1943 the original Baroque hall, which had been converted into offices in the 19th century, was renovated according to plans by the architect Bohumír Kozák. Further sensitive alterations, which included some restoration work, were undertaken between 1994 and 1998 under the leadership of the architect Pavel Kupka.
Work carried out by the GEMA ART GROUP a.s. experts concerned the stone elements on the façade of the Baroque Tuscan Palace. Prior to restoration a survey of plastering layers, tests of cleaning procedures and, in the case of the statue on the attic, a stability evaluation were carried out. Restoration of the statue “Musica”, work of the sculptor Jan Brokoff, was technically the most demanding part of the remit as it had to be removed from its setting on the attic.
Restoration of the sculpture “Musica”:
Restoration was needed for one of the seven statues placed on the attic balustrade. The sculptural group depicts allegories of the Seven Liberal Arts: Grammar, Rhetoric, Logic (or Dialectic), Arithmetic, Geometry, Astronomy, Astrology and Music. It dates back to the years 1689 – 1691 and was created by the Baroque sculptor Jan Brokoff. The statues are made from medium grain Žehrovice sandstone.
Despite the fact that the statue of “Musica” was last restored in 1997 it was now found to be severely unstable. This was due to the corrosion of the pin inside the statue: corrosion had caused the pin to expand and gradually crack the stone. The most extensive damage was found on the plinth. The statue had been placed on a pure cement base, which contravenes good stonemasonry practice.
To start with the statue was dismantled and moved to a restoration workshop, where it was cleaned and rid of unsuitable cement grouting. Deteriorated parts of the statue had to be reinforced and minor cracks infilled. Several fragments were reattached using epoxide resin glue. More extensive cracks were injected with suitable sealant. To conclude the restorers carried out localized retouching and applied hydrophobic agent. A new, anticorrosive pin, which holds the statue on the plinth, replaced the decayed original.
Stone coats of arms above the portals:
Restoration research carried out before the work commenced established that the coats of arms were made of two different materials: the coronets, added later, were made from either Hloubětín or Petřín sandstone, while the actual coats of arms of the Counts of Tuscany were carved in high quality silica sandstone from Dvůr Králové quarry. The difference in the quality of the stone was reflected in the degree of its decay. The coronets were entirely degraded; in contrast the individual coats of arms exhibited only minor mechanical damage.
Stratigraphy survey of the layers found evidence of the original monochrome dark red coating. Lower parts of the coats of arms are decorated with stuccoes which were added at a later date.
The coats of arms were first cleaned mechanically and then chemically using ammonium hydrogen carbonate. The coronets were strengthened overall by an application of organosilicates. Finally, the restored surfaces were retouched using iron oxides in order to recreate the original colouring.
Restoration of the stone eagles and heads of the portals :
These elements are part of the architecture of the stone portals of the Tuscan Palace. The sandstone was obtained from the Kamenné Žehrovice quarry. The necessary stratigraphy survey was carried out at the onset to evaluate the best possible method for the restoration. Mechanical clean-up was followed by reinforcement of the stone using organosilicates. Cracks were infilled with mineral grout. As previously, colour retouching and application of a hydrophobic agent concluded the work.