3 STUDY AREA
5.5.4 Globally Autonomous and Locally Interdependent Finca Inti
a. Registo fotográfico de patologias
Fig. 194– Tronco da escultura Atena, salientando a alteração superficial, a partir de fotografia de luz rasante.
Fig.195– Maior translucidez do fragmento possivelmente
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Fig. 197– Fractura e espigão de reforço de madeira no pulso
da escultura Posídon.
Fig. 198– Preenchimentos de lacuna na zona do pescoço e
cabelo da escultura Posídon.
Fig. 199 – Fractura do pescoço da escultura Atena. Fragmentação das massas de preenchimento.
Fig.200 - Escultura em alabastro de Nottingham com uma alteração superficial muito semelhante á encontrada no conjunto em estudo.
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b. Mapeamento do Estado de Conservação
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c. Pesquisa referente ao tratamento de limpeza
Tabela 6- Referências bibliográficas de misturas de solventes recomendados ou aplicados em intervenções de conservação e restauro em suportes de alabastro de gesso.
Referências Solventes /soluções
MASSCHELEIN-Kleiner, L., Los Solventes, Centro Nacional de Conservación y Restauración, Santiago de Chile, 2004, p. 134
Limpeza com Isoctano + isopropanol (1:1); em zonas mais manchadas etanol + água (9:1). Referente às soluções usadas na limpeza de uma escultura de S. Martin (Halle, St. Martinskerk) em alabastro.
HUBBARD, Charlotte, Alabaster Conservation. In
http://www.vam.ac.uk/content/jo urnals/conservation-journal/issue- 07/alabaster-conservation/
“With the results in mind, the cleaning of the figure therefore went
ahead with the white spirit emulsion, immediately rinsed with white
spirit.”
CALVO, Ana, Conservatión y Restauración – Materiales, técnicas y procedimientos de la A a la Z, 1ªed, Ediciones del Serbal, Barcelona, 1997, p. 18
“El alabastro es muy sensible al agua, por ello se puede intentar
limpiar con isoctano e isopropanol (50:50), llegándose a emplear en
casos dificiles, y com sumo cuidado, etanol y água (90:10).”
CURTEIS, Tobit, The Entrance Hall of the Fitzwilliam Museum, Cambridge: A Conservation Approach to Nineteenth- Century Architectural Polychromy, Journal of Architectural Conservation, nº2, vol.8, Julho 2002, p.7-22.
“On the alabaster sections, aqueous treatments were avoided and the
stone was mainly cleaned using white spirit on cotton wool swabs. In some areas where the dirt had become particularly ingrained, a
solution of 1:1 ethanol and acetone was used.” P. 12-13
ASHURST, John; DIMES, Francis G., Conservation of Building & Decorative Stone, Butterworth Heinemann, Oxford, 2001
“Alabaster, the surface of which is dissolved by washing with water,
may be cleaned with the soap and white spirit and finished with
white spirit alone on cotton swabs”. ASHURT, John, Cleaning masonry buildings, p.135
LARSON, John, The conservation of stone monuments in churches”, p.185-196:
“Alabaster (calcium sulphate) is water soluble and therefore
should never be cleaned with soap and water, which will slowly erode the surface. As alabaster is also very soft it should not be cleaned with abrasives, such as commercial abrasives containing pumice and bleach. Acid and caustic solutions should also be avoided because they will erode the surface and create, or exacerbate, staining. P.190;
“Limestones and sandstones are used in a wide variety of types
for monument construction. They differ from alabaster or marble in that some are porous. It is very noticeable in churches that it is the highly polished marble and alabaster monuments that suffer from surface erosion caused by condensation. The more porous limestones and sandstones absorb atmospheric moisture quite readily, and will also absorb any water from a cleaning treatment. Liberal washing can, for this reason, encourage salt crystal growths and staining from salts and iron. Similarly, the use of bleach, acids and powdered detergents can create problems in the surface pores of the stone
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which may not become apparent until several years later.” P. 190
“Chemicals such as white spirit, liniment of soap and ammonia wax
paste are very useful for cleaning alabaster because the surface is
relatively impervious”. John LARSON, The conservation of stone sculpture in museums, p.199-200
COX, Dennis, The Conservation of Alabaster. In
http://www.buildingconservation. com/articles/alabaster/alabaster.ht m-
“Alabaster should be cleaned using mild solvents. The type and
strength of solvents has to be determined by on-site tests but the most usual is a mix containing white spirit, de-ionised water and a small quantity of non-ionic detergent”.
LARSON, John, The conservation of alabaster monuments in churches, The Conservator, nº3, 1979, p. 28-33
“The safest solvent that can be used on alabaster is white spirit”. (…)”Often more effective than white spirit alone, is a mixture
composed of de-ionised water, white spirit and Lissapol. The water in this mixture is not harmful, because it is bound up with the soap
and white spirit. (…)”To remove the mixture, cotton wool pads
dampened with acetone or 50/50 mixture of acetone and white spirit
should be used. (…)”Unlike marble, alabaster is not adversely
affected by the use of solvents containing small quantities of ammonia. Linament of soap, when mixed with a few drops of ammonia, ir very effective for cleaning both pigmented and plain alabaster and will not aggravate iron staining. It should be neutralized with white spirit, or white spirit mixed in equal parts with
acetone.”(…)“Greasy dirt, beeswax and old varnish can be cleaned
by using water-soluble Nitromors (…) removed with white spirit
acetone”. P. 30
MARINCOLA, Michele, A Standing Virgin at The Cloisters - The Conservation and Restoring of a Medieval Alabaster
“Tests were carried out on the surface of the stone to determine
whether the Virgin could bem safely cleaned and also to establish whether any of the translucency of the alabaster could be reclaimed. A mixture of a small amount of saliva and several organic solvents
applied with a cotton swab reduced the discoloration.” (…)”Gentle
cleaning with a vinyl eraser (borracha), while the surface was still wet with this solvent misture, permitted the extent of the treatment to be carefully controlled and conducted without damage to the soft underlying stone.
SCHMID, Georg, Relatório sobre o actual restauro, p.232- 235, [em] Preservação Histórica em Baden-Wuerttemberg, Boletim de notícias de
Landesdenkmalamt, 2002, p.195- 265
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d. Testes de pastas de preenchimento
Tabela 7– Testes de diferentes pastas de preenchimento, com 6 tipos de adesivos com cargas de alabastro de gesso.
Poliester, Airocoll SL®
Paraloid B72® PVA Plexigum ® Primal SF016®
Paraloid B44®
Fig.201 – Exemplos de
alguns testes cromáticos das pastas de preenchimento (pigmento natural, alabastro
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