Historical Painting Techniques, Materials, and Studio Practice

Sa. Location : Salisbury west front,
north face of north turret.
Sb. Location : Salisbury, cloister boss.
2.Smm
I. White ground
2. Iron-oxide red
,,
I
lmm
1. White ground
2. Yellow ochre, gold size?
3. Gold leaf
4. Black decoration
Sc. Location : Salisbury central porch,
tym panum .
Sd. Location : Exeter west front,
drapery of king.
2.Smm
.
I
l.Smm
Multi-layered sample, with
1. Red earth primer,
2. White lead undercoat,
3. Vermilion top layer and several
repaintings of primer, white lead
and vermilion.
1. Pi nk primer
2. White lead
3. Vermilion
4. Black cement layer
Figure 5. Paint cross sections: a prelimillary view.
paint, but protected corners usually retain odd fragments, as was fo und on
the north return.
At this point in the investigation, the discovery of the existence of paint in
just one area on Salisbury west front could be the result of a poor technique.
The careful preparation of the stone with appropriate sealant, primer, and
ground played a major role in the durability of the paint layers above. The
initial examination of the north turret samples at Salisbury suggests that the
white ground is of a chalk and gesso type, and not very tough, though it is
thick and would have provided a smooth surface for the paint. Its softness
suggests a loss of medium, though the lack of evidence so far for paint elsewhere
may be due to a poor choice of medium.
Visual analysis, largely through the study of cross sections at this stage, reveals
a typical medieval palette, with a liberal use of costly exotic pigments, particularly
in the central porch. Pigments here include vermilion, verdigris and
copper resinate greens, black (probably lamp black), red and white lead, a dark
blue that appears to be indigo, red and yellow ochre, and gold leaf. The
cloister pigments include red and yellow iron oxide, black, gold leaf, a cool
blue-green and a calcium carbonate white. No lead pigments have yet been
identified here. Only two pigments, red and yellow ochre (with a chalky
white layer below), have been identified on the west-front facade.
Exeter polychromy
That any paint survives at Exeter, in spite of several major cleaning programs,
must be due to a careful selection of superior quality materials (Fig. Sd) with
abundant use of durable red and white lead. Most samples are well bound,
though migrating salts and some loss of medium cause some paint to delaminate.
A typical sample from Exeter west front has-on top of an invisible sealanta
red earth primer followed by a pale pink primer consisting of iron-oxide
red, chalk, white and red lead, all in varying proportions (Plate 22). On top
Sinclair 107