Page 86 - Tibetan Thangka Painting Methodsand Mat, Jackson

The chief yellow pigment of Tibetan painters was he used to soak it in water and then use his fingers to
orpiment, a natural yellow trisulfide of arsenic, As S3' rub off the smooth, clay-like outer layers that had
z
Deposits of orpiment occur near the surface of the earth, become saturated and soft.
especially near hot springs or in the vicinity of silver The related earth colour red ochre (btsag) was
deposits. In Tibet the most famous deposits were found also well known in Tibet. Chemically, red ochre is
in East Tibet, near Chamdo. Large quantities of identical to yellow ochre, except that the red lacks the
orpiment are also said to have been mined at Shih- hydrous content of the yellow. It was a cheap pigment
haung-Ch'ang in Yunnan Province in China. 37 that was often employed like whitewash for painting the
The mineral orpiment is easily identifiable by its outside of large buildings. Red ochre too was not widely
yellow metallic lustre and its strong sulfur-like smell. used in thangka paintings in recent times. Investigations
It is also very soft (1.5 - 2 on Moh's scale). There are a of older paintings, however, have indicated its presence;
variety of qualities; in Tibetan painting as in Tibetan in the study by Mehra red ochre showed up in five of
medicine the pure, intensely yellow orpiments were the eight museum thangkas chosen for examination. 40
best, while the greenish and reddish varieties were
inferior. 38 Due to its eye-catching appearance and its
Earth White (ka rag)
chemical properties (like vermilion it could be artificially
produced by sublimation), in early times orpiment was
the object of alchemical speculations in China and
elsewhere.
Orpiment always occurs in nature together with
realgar, the closely related red sulfide of arsenic. Both
orpiment and realgar were formerly used in European
painting, but being highly poisonous their use has
actually been outlawed in many places. However, in
Tibet where European synthetic yellows do not seem to
have penetrated in appreciable quantities, orpiment and
realgar continued to have a wide application down to
recent times. Realgar, it should be added, was not
commonly used in thangka painting by our Central
Tibetan (dbus pa) informants. For them, its widest
application was in the painting of walls and wooden The main white pigments in Tibet were calcium
surfaces. compounds. The most common white was a mineral
Orpiment and realgar had certain medicinal uses called ka rag, which seems to have been a high-grade
in the Ayurvedic medicine of Tibet, but most painters white chalk. Like limestone and marble, chalk is basic-
also knew the pigments to be harmful if ingested in any ally calcium carbonate, but chalk is not to be confused
quantity. Therefore, although many painters licked with lime (rdo zho or rdo thai), the white oxide of
their brush tips while applying other pigments, most calcium that is made by heating limestone in a kiln. 41
were careful not to get any of these arsenic compounds In Tibet, the best known and for painting the
into their mouths. most valuable ka rag came from Rinpung (Rin-spungs),
When preparing orpiment for use as a pigment, a place roughly half way between Utasa and Shigatse
the artists ground it in the dry state. It could be ground that in the 16th century was the seat of the rulers of
3
vigorously, 9 but when ground extremely finely the Tibet. In parts of Tibet the fine grade of ka rag from
richness of its yellow was slightly diminished. Rinpung was quite costly; in the town of Shekar Dzong
(shel-dkar rdzong) in Western Gtsang, for instance, the
Yellow Ochre (ngang pa) pigment was said to cost weight for weight as much as
butter. Therefore for purposes that required a lot of
white, such as the preparation of the ground, painters
Yellow ochre is a fine-grained earthy variety of the commonly substituted less expensive grades of white.
mineral limonite, a hydrated ferric oxide. Although According to the artists there were two main
ochres have been popular among Western artists for varieties of the ka rag mineral: "masculine" (pho) and
some centuries, Tibetan thangka painters seldom used "feminine" (mo). The masculine type (pho rag or
them as pigments in their own right, preferring the more pho dkar) was harder and coarser, while the feminine
intense yellow of orpiment. Nevertheless, yellow ochre (mo rag or mo dkar) was relatively soft and fine.
was widely used as the main undercoat for gold. However, when the masculine was left out to weather
In Central Tibet the most highly prized yellow in a stream bed or in some wet place it would convert
ochre (ngang pa or ngang sang) came from the Zhwa-lu to the feminine, becoming. lighter and softer. If the
district of Gtsang; hence the name, zhwa lu ngang pa. artist wished to effect this change even faster, he would
Because it had a very soft and earthy consistency, this first soak the pho rag in water for a few days, At first
pigment did not require much grinding. In fact, one the phD rag made the water turn yellow, and when this
painter stated that instead of grinding it in a mortar, happened the discoloured water had to be poured out

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