Colnaghi Foundation Journal 03 - Magazine - Page 165
162
Scientific intervention in two major Murillo canvases
This was achieved in the restoration process, recovering
the light and colour of both pictures so that previously
invisible details and aspects are now apparent, in this
way revealing Murillo’s technique and consummate skill.
AN OPPORTUNITY FOR KNOWLEDGE, A TOOL FOR
INTERVENTION AND MANAGEMENT
The two works are among the most impressive items
in Murillo’s oeuvre, universally regarded by scholars
as providing significant insight into the artist’s
creative process – all the more so since they have
never been subjected to intervention in their entirety.
This kind of project affords a unique opportunity
to broaden knowledge of the works, since it enables
in-depth research from every angle. The purpose of
this contribution is to permit broader access to the
information gained from conservation and restoration
based on a scientific and critical point of view.
As mentioned above, when conservation projects
are undertaken on objects included in the Catálogo
General del Patrimonio Histórico de Andalucía,
systematic and planned management is required.
Interdisciplinary teams collaborated on putting
together a programme for both canvases with their
respective frames; this entailed the description of
the works, assessment of their cultural value, and
diagnosis of the state of conservation. The project
team also laid out the proposed intervention on a
critical, and scientific basis, ensuring that it was
systematically planned and sustainable, in order
to enhance the formal, aesthetic appreciation in
proportion to the works’ value in both historical and
material terms.
The canvases were removed from their original
location in December 2016. Subsequently in JanuaryFebruary 2017 research was carried out, and a plan
for conservation treatment settled on. Upon approval
of this by the Comisión Provincial del Patrimonio
Histórico, the operational and training phase of the
project began. Guided visits of the works commenced
in July 2017, and treatment of the canvases and frames
was concluded by December 2017.
RESEARCH AND IMPLEMENTATION
The two phases of the project, research and
implementation, were based on several general
criteria, with special importance given to study prior to
intervention and maintaining the integrity of the work
and all its values.
Scientific intervention in two major Murillo canvases
163
An informed basis for the intervention was made possible
through the contribution of each and every team
member, including specialists in restoration, history,
image, chemistry, biology, preventive conservation, etc.
Study prior to the intervention took into account the
material nature of the objects and integrity of all the
values attached to them, both intrinsic and acquired.
IAPH conservation was carried out in compliance
with the study and intervention methodologies that
the organization has developed, together with the
application of current international criteria. It is
generally accepted that intervention should never be
done arbitrarily, but must be supported by studies
which aid understanding and knowledge of the
cultural object. Intervention will not be one hundred
per cent effective unless there is understanding of the
causes giving rise to changes, and adequate knowledge
for the conservation of the object. This knowledge
comprises not only how to intervene directly (curative
or conservative intervention, as appropriate) but also
more indirectly, what kind of environment is needed
to guarantee conservation and enable appreciation
(preventive intervention).
GAINING INSIGHT INTO THE ARTIST’S
CREATIVE PROCESS
The significant research component of the project is
evident from the breadth of technical and scientific
studies done by various specialized departments of
the IAPH Intervention Centre. These studies allow
us to deepen our understanding of Murillo’s working
methods, re-discovering his artistic virtuosity.
The first phase of non-invasive analytical methods,
minimizes the number of samples taken in the second.6
The Chemistry Laboratory’s work here should be
highlighted, involving substantial scientific innovations
and collaboration. Scientific analysis of the constituent
materials was carried out following the methodology
recommended by Spanish Historic Heritage Law
16/85. In compliance with this, non-invasive
techniques and methods were applied in the first
phase, so that chemical identification was done without
samples or contact with the surface. Thus, the essential
preservation of the works’ integrity was reconciled with
the deepest possible exploration of the materials.4
Since these types of non-invasive techniques render
only a superficial knowledge of materials, these
analyses have to be complemented by a second phase
of stratigraphic analyses yielding information about the
complex multi-layered system of the polychromy.5
Fig. 3 / Portable X-ray
fluorescence scanner
(MA-XRF) using LANDIS-X.
A detailed analysis of the works was carried out using
the innovative technique of macro X-ray fluorescence
scanning (MA-XRF), with a mobile device showing
elemental images of the paintings in real time (fig. 3).
This was complemented by XRF spot analyses7 and
mobile Raman spectroscopy, thanks to the collaboration
among various research centres and both Spanish and
international Universities.8
The results show that the ground and priming layers9
in both works are made up of iron aluminium silicates
with amounts of calcite and carbon black which vary
according to the area.10 A small proportion of pyrites
and ilmenites, minerals naturally occurring in the
clays of the pyrite belt round Seville and Huelva, was
identified. These compounds have been identified in
other works by Murillo, Velázquez and Zurbarán11
and can be considered as distinctive elements in
compounds made up of earths from Seville which
differ from other materials found in nearby locations.
The stratigraphic study was carried out in cross-section,
using optical microscopy (O.M.), electronic microscopic
scanning with microanalysis (SEM-EDS), infra-red
spectrometry with a Fourier transformer (FT-IR)
and gas chromatography with a detector of mass
spectrometry (GC-MS).
Priming was applied in two layers with the addition of
lead white as a siccative. In some samples, remains of
pigments were found which were possibly re-used from
palette leftovers. The tone of the priming layers varies
from area to area, depending on the amount of lead
white, calcite, and carbon black added.
