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By way of introduction to the block of studies on the
technique of the Theodori's panel paintings it is necessary
to draw attention to the open nature of a number
of the problems. The extensive restoration work which
has been under way in the Chapel of the Holy Rood since
1979 is gradually expanding the state of knowledge as
to details which have not yet been studied. This unique
set of pictures, plastic decorations and incrustations
of precious stones, ascribed in general to the authorship
of Theodoricus, is beginning, in the course of the restoration,
to be separated more clearly into parts done by several
different hands, i. e. several artists, led categorically
by the programe set by the leading Master, as indeed was
the idea which Antonín Friedl attempted to study years
ago. Inter alia the question has arisen of the originality
of the pastiglia, the differentiation of the periods of
origin of individual alternations, and the problem of
the date of the actual completion of the decoration in
the Chapel. We are trying today to reconstruct in great
detail the actual process of the technical realisation,
influenced also by changes in the programme of decoration.
As an introduction to the problems we should like to refer
to the basic works by Bohuslav Slánský and Mojmír Hamsík,
which are quoted in the bibliography of the first issue
of this yearbook, and also to the art historical works
of A. Matějček, J. Pěšina, A. Friedl and K. Stejskal,
as well as numerous other pieces of literature quoted
in the individual articles.
The attentive reader will notice certain differences of
opinion between the authors imparting their findings here,
conditioned, inter alia, by what part of the material
they came into closer contact with. The fears connected
with the premature publication of findings which differ
are, in the opinion of the editors, unfounded as the differences
in opinion can only be beneficial to the exchange of standpoints
on academic ground. It rather goes to show that our field
is working its way out of the period of isolated research
by individuals and into exact dialogue and mutual verification.
The precision instruments which historical art technology
now has at its disposal consist not only of laboratory
analyses, but also in the detailed study of stratigraphy,
in the interconnection of historical sources. This precise
comparison of partial findings is still before us.
author
The Editors (J.D.)
PASTIGLIA - ORIGIN AND TECHNIQUES
Relief decoration, called pastiglia pastillaye, yesería,
relieve en stucco, applique relief, plasterreliefis a form
of sculpture set in the painting or rather a proof
of a special conception of synthesis of the two.
This has been a source of interest to a number
of researchers, and it has been studied from various points
of view since the seventies, always in connection with
Byzantine painting 1.
M. Frinta has convincingly explained the origin of this
plaster relief in the eastern Mediterranean region in
a series of works 2.
This author attributed the spread of the technique of
relief decorations to the Crusades. The »Crusaders art«
sank roots in many places along the routes of the Crusades,
especially in Mediterranean ports and spread asfar as
Spain where the technique of pastiglia appeared in Catalonia
from the 13th century. Another important centre was Naples
from where, it would seem, the popularity of relief decorations
spread further north, to Pisa, Florence and Siena. In
the 14th century it reached the Netherlands, the Rhineland
and Westphalia. We can find examples of pastiglia in England,
too, already from the end of the 13th century, and English
scholars have often linked that to strong Italian influences
3.
It is not clear why this popularity reached such remote
regions, continued for centuries and was not necessarily
bound to any style 4.
For Bohemian Gothic painting the problem is interesting
particularly in relation to Master Theodoric, and his
circle. This paper sets out to recapitulate the existing
results of the study of pastiglia in European painting
and to characterize this technique on 14th century panel
and mural painting in our country.

Master Theodoric, Adoration of the Magi. Detail, painting
in the Holy Rood Chapel at Karlštejn Castle, before 1367.
Pastiglia of the silicious material.
Proofs of the substance of pastiglia as imitation of metal
decorations on the oldest icons were gathered by M. Frinta
in his work on Cypriot icons. (He drew attention to the
significance of ornamental motives on those metal decorations
for the flat relief of the gilded background)5.
The author discovered that apliqué relief does not exist
in the very centre of Byzantine culture, in Byzantium,
only in the marginal regions such as Cyprus and the Sinai
Peninsula. Its popularity continued longest on Cyprus,
for five centuries beginning in the 13th century. It seems
that in the eastern conception that is not known in the
western type of plasticity the pastiglia take the form
of low relief with added painting, which is also known
from the oldest examples of Balkan icons. In Western Europe
the appearance varied from the middle of the 13th to the
middle of the 15th century when the eastern reminiscences
vanished.
The technique and the material composition differs from
region to region and seem to have depended on the availability
of suitable material. Each region drew on local supplies:
customary for northern Europe is common white chalk or
grey mountain chalk, for the southern region, gypsum (gesso).
The technique is simillar as can be deduced from the description
in Cennino Cennini's Book on Art, where a total of
eight chapters is devoted to pastiglia. The author of
the manuscript describes three basically differing techniques,
the application of relief with a brush, the impression
of a stone mould into tin-plate and finally the casting
of relief from a mould. There is a broad selection
of material: for the application of relief with a brush
to the panel picture they used fine gesso, on the wall,
lime with sand or a mixture of flour and varnish,
occasionally wax and resin 6.
For both purposes relief was suitable that was
imprinted from a stone to the tin-plate which was
then filled with gesso and attached with ship pitch. Gilding
was carried out on an oil base. As comparative material
the most interesting for us is the description of the
preparation of the relief cast of gesso for application
on a panel picture. The bonding agent is »stronger»
glue, the mould is made of clay, insulated with non-solidifying
oil used for lighting; the attachment was carried out
with fine gesso identical with the ground for painting.
The Italian manner of applying fine runny plaster with
a brush has been proved by detailed analyses carried
out in the laboratory of the London National Gallery 7.
Rich comparative material is provided by Catalonian panel
painting from the 13th to 15th century. The technique
of applying plastic ornament (relieves de estuco) with
a brush to black linear preparatory drawing is shown
on the altar front in Neo-Byzantine style from the early
13th century of Chio at Huesca. In the mountain regions
of the Pyrenees diocese of Lérida a characteristic
simplified technique of gold glazing (corladura) has survived
on metallic, most probably tinny foil that covers the
relief surface 8.

St Jerome. Detail of the wall painting »Maesta« by Simone
Martini in Siena plaster of gypsum (»gesso«) and real
parchment.
The technique of casting prefabricated pastiglia from
chalk bonded with glue can be shown on the St Clare altar
in Cologne cathedral in the Rhineland; this appears on
the inner side of the movable wings where the painting
is carried out on canvas. The siting of the individual
plastic motives is pre-drawn with a linear network
engraved in the chalk ground. Remnants of metal foil have
been found on the surface of the pastiglia, probably used
as insulating layer in casting. The gilding is carried
out on a oil layer coloured with red lead. The altar
dates from the middle of the 14th century and is a combination
of painting and sculpture. Christa Schulz Senger 9
is of the opinon that the impression of the relief decorations
is strikingly similar to the gilded metal reliquiaries
in the same cathedral.
The connection of pastiglia and the original metal decorations
is proved at Karlštejn Castle by the existence of pewter
relief ornaments in the back ground of the picture of
St Simon in the Holy Rood Chapel 10,
whose position is determined by the engraved and punched
squares on the gilded background with which they originally
blended, for their surface was likewise gilded. According
to restorer Jan Pasálek, there are remnants of metal relief
ornaments also on the mural paintings in the same chapel.

Macro-photos of plastic elements on Theodoric's paintings.
Above tinny applique on the picture of St Simon, below
siliceous pastiglio of the sword on the picture of St
Catherine.
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The Holy Rood Chapel at Karlštejn Castle before Mocker's
renovation (from Neuwirth's publication, 1896, PI. XXIX)
A number of authors have mentioned the relationship between
pastiglia and goldsmith's art. Vlasta Dvořáková, speaking
of the Hungarian and St Wenceslas Chapels in the cathedral
at Aachen, which arose on impetus of Charles IV and were
decorated with panel altarpieces, says that the common
feature of these reliquiary icons is a relief background,
relief ornaments on the garments, the application of precious
stones and partly gilded metal plate set in the area of
the painting« so that... »they came close in execution
of goldsmith's work of the Italian-Byzantine character
11.«
Often stress is laid on the symbolical meaning of gold
and precious stones as supra-natur al matter representing
a higher, imaginary world. The same meaning was clearly
achieved by the pastiglia with their gold foil cover.
Karlštejn Castle is an example of the combination of precious
metal in the form of crosses, buckles, and perhaps even
crowns, nimbuses and rays and the technique of gilded
pastiglia used on the background of the panel pictures
on the linking panelling, the edges of precious and semi-precious
stones, on the mural paintings, 12
the ceiling and on the stone elements of the architecture.
Detailed investigations in the laboratory of the National
Gallery in Prague have shown that the composition of the
pastiglia on Theodoric's panels in the Holy Rood Chapel
is considerably varied 13
The basic types of material are chalk, and silicious clay;
there are also combinations with various pig ments. A
mixture of pigments alone is rare. These two basic types
can be found on the same panel, even alternating according
to the kind of ornament on the garments. The pigments
used are red and yellow ochre and minium; the bonding
agent of the chalk is solely glue while silicious material
is bonded with starch and egg-white with an admixture
of oil The mixture of pigments alone contains only oil.
There is an important finding that the silicious material
of the infill is in its detailed composition, i.e. an
admixture of yellow and red ochres, black particles and
calcite, and in the kinds of bonding agents, comprising
starch, egg-white and oil, entirely identical with the
lower strata of the ground of the painting. Of the twenty
pictures under re-seach seventeen had this composition
oftheplastiglia, irregardless of the fact that were on
a chalk priming, on silicious layer or direct on
the wood. An exception to this was the picture of Apostle
Luke where they found a mixture of yellow and red
ochres bonded with starch and oil and coagulated chalk
with the same pigments and identical bonding agent. Another
exception were the metal ornaments on the picture of St
Simon and the newly reconstructed chalk pastiglia of St
Paul that differs already in external appearance, namely
in the sharp outlines of the relief.
These data refer to the decorations of the background;
in the composition of the pastiglia inside the area of
the painting laboratory tests have shown a predominance
of chalk bonded with glue. Silicious material is in the
minority, there are exceptional mixtures of pigments (yellow
ochre, minium) bonded with oil. All pastiglia on the area
of the painting are glued to a layer composed of
red and yellow ochres and minium, occasionally with an
admixture of lead-tin yellow bonded with oil and rosin.
In all cases this is a type of cast, prefabricated
ornament made in series, differing in number according
to the size of the motive and amounting to up to nine
pieces. The black amorphic matter on the surface of several
paltiglia has been identified in the laboratory as metamorphozed
tin, which indicates that metal foil was used as insulating
material.

Master Theodoric, St Helena (Holy Rood Chapel
at Karlštejn, 1365-67). Photo Čestmír Šila
Since essential restoration work was carried out at Karlštejn
Castle in various historical periods, the question of
the origin of the plastic decorations has been raised,
the more so after the discovery of tiny fragments of gold
foil on the edge of the figures; certain restorers in
recent times have had romantic ideas about the original
appearance of the pictures. In addition, the fact that
the chalk priming layer is cut around the outline of the
painting in about a half of the pictures in the Holy
Rood Chapel has led to a number of speculations as
has the discovery that the pastiglia and their gilding
in some cases cover the edge of the painting.
On the question who made these gilded decorations interesting
ideas have been put forward by Mojmír Frinta 14
suggesting an equal evaluation of, the painting and the
ornamental gilding. Two signatures have been found on
the »Monteoliveto« altar, one referring to the painting,
the other the gold ornaments. A painted cabinet with rich
pastiglia is also signed twice; it derives from the town
hall in Siena. A further proof of collaboration between
the painter and the artist who made the apliqué relief
is, according to M. Frinta, the »Maesta« of Simone Martini,
again in the Siena Palazzo Pubblico and his Madonna with
Saints in the lower church at Assissi. The application
of plastic adornment on the mural painting of the Maesta
prchaly arose after a certain lapse of time, to judge
by archive records of expenditure and here, too, the reliefs
cover the painting in places. At Karlštejn Castle, too,
one should assume broad collaboration between specialized
masters and their assistants. The demanding nature of
the work required a division of labour where not
always the binding method of material composition was
adhered to, as shown elsewhere 10.
author
Mojmír Hamsík, AHVT A 027 (T.G.)
1 D. T. Rice, Cypriot Icons with
Plaster Relief Backgrounds, Jahrbuch der österreichischen
Byzantinistik, XXI, Vienna 1972. A. Grabar, Les revetements
en or et en argent des icones by/antines du moyen age,
Venice 1975.
2 M. Frinta, Relief Imitation of Metallic Sheathing
of Byzantine Icons as an Indicator of East-West Influences,
The High Middle Ages, Acta, Vol. VII, 1980.
M. Frinta, Raised Gilded Adornment of the Cypriot Icons,
and the Occurence of the Technique in the West, Gesta,
International Center of Medieval Art, Vo.XX/2, 1981.
M. Frinta, Relief Decoration in Gilded Pastiglia on the
Cypriot Icons and its Propagation in the West, Acta of
the Second Congress of Cypriot Studies, Nicosia 1986.
3 Amanda Simpson, English Art during the Second
Half of the 14th Century, Resultatband zur Ausstellung
Die Parler und der schöne Stil 1350-1400, s. 137-159,
Köln 1980. P. C. Van Geersdaele, L. J. Goldsworthy, The
Structure, Pigments and Medium of some Samples from the
St. Stephen's Chapel Wallpaintings in the British Museum,
The Conservator, Vol. 2, 1978, s. 9-12. The St Stephen
's Chapel at Westminster, dated to the middle of the 14th
century, was adorned with rich relief decorations, as
shown by frag ments of the story of Job now in the British
Museum. Analyses of the material composition of the pastiglia
have brought the surprising discovery that it is a mixture
of minium and lead white bonded with oil and an admixture
of egg-yoik (Van Geersdae..., op. cit. – see above)
4 An example of the relatively late use of plastic
decorations in the form of vine tendrils are the panels
with the Deposition in the Tomb in the museum at Ipswich,
dated to the first half of the 15th century and following
the West European type in style.
5 M. Frinta, The Decoration of
the Gilded Surfaces in Panel Painting around 1300, Europäische
Kunst um 1300, CIHA; Wien 1983, s. 69-75.
6 A related technique of relief decorations made
of wax and resin is found e.g. in 15th century Spanish
panel painting particularly on statuary of the Hispano-Flemish
circle, Alsace and the Rhineland (M. Frinta, The Use of
Wax... see above). In the author's view the decorations
were prepared with the aid of stamping dies on a
thin layer of wax with an admixture of resin, then cut
apart and applied to the surface of the panel or the statue.
The advantage was considerable elasticity that facilitated
the shaping of the complex Late Gothic folds. A similar
technique of pastiglia of red wax, which contains minium,
is described by Anne Brodrick and Josephine Darrah in
their work on the tomb statuary of the Duke of Arundel
William Fitzalan and his wife: Church Monuments, Vol.
1, 1986, pp. 65-94. The authors are of the opinion that
the relief adornment was cast in a metal mould. Tin
plate has survived on the surface of the pastiglia, and
this was covered with oil gilding. The tin might have
served as insulating layer.
7 Art in the Making, Italian Painting before 1400.
D. Bomford, J. Dunkerton, D. Gordon, A. Roy, Jo Kirby.
National Gallery, London 1989-90. The authors assume that
the pastiglia on Jacopo di Clone's Crucifixion were composed
of a mixture of lead white and gesso.
8 Miguel A. Alarcia, Museo de arte de Cataluna,
s. 3-11.
9 Christa Schulze-Senger, Der Claren-Altar
im Dom zu Köln, Kölner Domblatt 1978, s. 23-36. On the
Relief Adornment in the Klarenaltar and Other Paintings
in Cologne ve sborníku Die Kölner Maler von 1300-1430,
Köln 1976, s. 131-139.
10 M. Hamsik, Theodorik a dílna – addenda
k technice malby, Umění XXXIV, 1986, s. 64-68.
11 V. Dvořáková, Karlštejn a dvorské malířství
doby Karla IV, in: Dějiny českého výtvarného umění 1/1,
s. 320, ČSAV 1984.
12 M. Hamsík, J. Tomek, The typical material of
the pastiglia on Theodoric 's panels, i.e. silicious clay
with an admixture of yellow and red ochres bonded with
starch, egg-yolk and oil, is entirely identical with the
material of the pastiglia of the mural paintings in the
Holy Rood Chapel at Karlštejn Castle and in St Vitus'Cathedral
in Prague.
13 The Puzzling Raised Decoration in the Paintings
by Master Theodoric, Simiolus 8, 1976, s. 271-300.
14 M. Frinta, Stamped Halos in the 'Maesta' of
Simone Martini, Atti del convegno, 1988, s. 139-145. The
material of the relief decorations of the maesta is discussed
by E. Borsook – in the author's view it is gypsum. According
to verbal information of restorer Camilla Tarozzi of Bologna
there simultaneously existed in the Italian technique
of the first half of the 14th century wax bon děd with
Bologna chalk as material for pastiglia, e.g. in the mural
painting of Vitale da Bologna.
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