Proceedings e report - Firenze University Press

EFFECTS OF THE THERMO LIGNUM® WARMAIR TREATMENT ON ART OBJECTS WITH PAINT AND GILT FINISHES
3. Samples
The examination was carried out on 11 historical objects with a variety of finish assemblies as well as
on newly prepared samples. In the case of the latter, resins and glues were applied individually and in
combination as complete finish assemblies to Swiss pine or arolla (Pinus cembra). In some instances,
glass and canvas were also used as substrate material. Given the local geographical importance of pine
as work material in the Alpine region, and in order to create a “worst case” scenario (high resin
content in this type of timber), Pinus cembra was chosen as substrate timber for the purpose of this
investigation. Table 1 provides a description of the historical objects which were examined. Table 2
provides an overview of the coatings applied to the newly made samples.
Table 1: Description of the historical objects examined
Object No. Date/Period Description Assembly
A1 1900 Square altar section Chalk (Black Chalk) ground
(Steinkreide grundierung) + gilding
A2 1680 Blossom Gold on varnish , glue + chalk
(Black Chalk), several thick layers
of gesso ground + gilding
A3 1770 Ornament Gesso + gilding
A4 1670 Acanthus leaf Glue foundation + gesso + gilding
A5 1756 3 Altar sections Glue foundation + chalk (Black
Chalk) ground (Steinkreide
grundierung + Polonaise gilding
A6 18 th + 19 th C. Finger 2 finishes, original 18 th C layer,
repainted in 19 th C
A7 18th C. Large top section of an Gesso + marbling with casein
altar with marbling method
A8 2 nd half 19 th C. Casing fragment White and gold
A9 2 nd half 19 th C. Foot fragment White and gold
A10 2 nd half 19 th C. Rosetta fragment Gold on pressed cardboard
A11 2 nd half 19 th C. Snail fragment White and gold
On pine
O
n
l
On
canvas
Table 2: Description of the coating variants
Type Variant No. Description
Resins
R1 Shellac
R2 Mastic
R3 Dammar
R4 Copal
R5 Sandarac
Glues
G1 Bone glue
G2 Rabbit skin glue
Combinations
C1 Gesso (Bologna chalk/Rabbit skin glue) +
gilding
C2 Gesso (Bologna chalk/Rabbit skin glue) +
oil finish
Glues
G3 Carp glue
G4 Sturgeon glue
"Combination aged and
C3 Oil paint on primed canvas (with zink
consolidated "
oxide white) – consolidated with carp glue
C4 Oil paint on primed canvas (with zink oxide
white) – consolidated with sturgeon glue
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