Historical Painting Techniques, Materials, and Studio Practice

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Figure 3. Three-dimensional spectrum of na sample from The Twentieth King of Shambhala.
Denman Waldo Ross Collection, Museum of Fine Arts, Boston (06.334).
orpiment nor realgar was fo und by PLM. The FTIR spectrum showed kaolin.
The remainder of the sample was analyzed by XRD. The majority of the
peaks correlate with those of metahalloysite. The remaining peaks were assigned
to kaolinite and arsenolite (As203), a white mineral. It is unlikely that
arsenolite is original to the painting. The yellow orpiment probably faded
and became a whitish arsenic trioxide. The impermanence of arsenic trisulfide
has been documented elsewhere (22).
Reds. Two shades of red are observed on the Shambhala paintings. One is a
bright red, the other is muted. The bright red uses the notation ga (rgya mtshal)
for Chinese or Indian vermilion (23). Ga is found on fourteen paintings and
depicts a color used for garments, lotus petals, and nimbuses. PLM, XRD, and
FTIR identified the color as a mixture of vermilion and kaolin. Under the
microscope, the vermilion particles appear as finely ground spherical particles
with a deep orange-red color. Several historical references are given by Jackson
and Jackson which state that Tibetan painters had access to both synthetic
mercuric sulfide and to the natural mineral cinnabar from China, India, and
Tibet (24).
The darker red is denoted by ma (dmar po), meaning red color (25). Ma is
found on fourteen paintings and describes a color used for garments and
sashes. The paint consists of a dual layer with a dark red organic coating over
a red pigment layer consisting of vermilion and kaolin. Further analyses are
pending and no conclusive identification has been made.
Pink. The color pink is used mainly fo r clouds but also for jewels, buckles,
makaras, and garudas (26). Pink is denoted by na or, occasionally, na kar, and
represents lac dye (na rosy mixed with a white pigment (27, 28). Na is fo und
on all twenty-three Shambhala paintings. Areas were sampled on six of the
paintings and examination of dispersed pigment slides revealed a clay base
mixed with a red dyestuff. FTIR analyses identified the clay as kaolin, as
described earlier. Identification of the dyestuff was achieved through absorption
spectrometry. The identification was fu rther confirmed by fluorescence
.spectrophotometry, utilizing a method described elsewhere (29). The pink
was identified as a lac dye. Figure 3 shows a three-dimensional plot of the
result, which is characteristic of lac. Jackson and Jackson state that much of
the dyestuff was traditionally gathered and prepared in Tibet (30). The dye
is extracted from sticks encrusted with a resinous secretion produced by the
lac insect, Kerria laeea Kerr.; the resin is still found today in the eastern Himalayas
where the warmer climate is more conducive to its fo rmation.
Orange. The color orange is represented by la, an abbreviation for the Tibetan
word fo r minium i khri) (31). The notation was uncovered on garments,
nimbuses, finials, crowns, flames, belts, jewelry, roof tiles, wheels, and vases. La
was found on fifteen Shambhala paintings. Three sampled areas were examined
by XRD, EPMA, FTIR, and PLM. The results identified a mixture of
Duffy and Elgar 81