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CHINA

The

temple

is

located

in

Wayao

village,

in

the

Sichuan

region,

and

it

consists

of

two

stories,

both

of

them

painted.

The

restoration

project

was

part

of

the

training

program

state

of

preservation

The

quality

of

the

wall

paintings

varies

remarkably

from

the

first

to

the

second

floor.

The

paint

layer

on

the

first

floor

is

much

rougher

than

the

second

floor

and

the

style

of

painting

appears

to

be

much

more

recent

than

the

upper

floor.

Inconsistencies

in

the

pictorial

cycle

of

the

images

on

the

first

floor

suggest

that

it

was

probably

repainted.

The

structural

wall

of

this

temple

was

made

of

stones

piled

up

apparently

without

binder.

On

top

of

the

stones,

a

coating

of

clay

mixed

with

straw

was

applied

to

create

a

kind

of

even

surface

to

host

the

pictorial

layer.

The

thickness

of

this

coating

varied

greatly,

according

to

the

voids

created

by

the

irregular

stones

constituting

the

wall.

The

binder

of

the

paint

layer

in

all

the

stories

was

water

based

as

taht

is

the

tradition

with

most

of

the

Tibetan

art.

First

story:
the painted surface covered the four walls. Nearly half of the preparatory layer was heavily detached from the stone based wall and many areas would not sound still, thus being in risk of falling off. The paint layer presented over paintings on the main deities: due to damages, local artists had painted over them to allow the local community to worship their deities. Dust deposits and cobwebs were spread all over the surface of the paint layer. The architraves were painted as well in such a rough way that many drops of enamel had been spilled over the paint layer.

Second

story:
the painted surface covered three walls only for there was a huge altar all along the forth one. The state of preservation was extremely appalling for the wall paintings had been subjected to vandalism acts and they were severely damaged. More than 30% of the paint layer was randomly detached from the stone based wall and several cracks were present on the painted surface. The protective varnish turned brownish with ageing and it would impede a clear vision of the pictorial cycle. On top of that, the wall paintings had been over painted with writings in Chinese and Tibetan with a deep red color.

Furthermore,

the

paint

layer

was

covered

with

a

thick

coating

of

mud,

in

some

cases

more

than

3

mm.

Oral

memory

from

the

local

community

recounts

that

this

story

had

been

used

as

a

kitchen

for

a

long

time

so

that

almost

everything

in

the

room

was

covered

by

black

soot

and

grime.

Luckily,

the

coating

of

mud

had

protected

the

murals.

Local

people

had

tried

to

clean

that

coating

and

the

black

soot

as

best

as

they

could.

As

a

consequence,

they

managed

to

damage

seriously

the

lower

section

of

the

paint

layer

on

all

the

three

walls.

On

the

south

and

west

side,

some

patches

of

painted

canvas

were

pasted

onto

the

wall

paintings.

Wooden

ceiling:
the ceiling in the second story is made of a series of interlocked wooden painted panels. The majority of the panels were over painted in 2004 and only 3 panels depicting mandalas had been left untouched. After some cleaning samples were carried out, it came out that all the panels still presented original paintings underneath. Although all of them were heavily darkened from the application of a very old and altered varnish, the paint layer was still looking in good conditions. Between the varnish and the over paintings laid a thick deposit of soot from smoke.

intervention

of

restoration

First

story:
the preparatory layer was fixed back to the stone based wall through injections of mortars and gluing solutions based on PVA binders. The small detachments were filled up with an acrylic emulsion dispersed in water. As for the deepest detachments, they were filled up with a mortar composed of local clays and a PVA binder. Tests were carried out to find out the most suitable clays to be injected. The mortar was then made of 2 kinds of local clay mixed with a PVA binder. Prior any injection, a surfactant solution was instilled through syringes. Where it was possible, existing cracks were used for the injections but in most of the cases, holes had to be done using hand-drills with bits whose width varied from 1 to 2 mm of diameter. Care was taken while drilling in order not to damage important outlines, figures or inscriptions. Since the amount of water in any mortar or solution would evaporate, some detachments could still not sound still underneath the surface of the wall paintings. Thence, the consolidation was checked every few weeks for the whole length of the project and more injections were carried out where needed.

Second

story:
the consolidation of the wall paintings was more complicated in this case for the paint layer was covered by a thick layer of mud and it was not possible to drill without risking to pierce important images or inscriptions. Thence it was decided to carry out the removal of the mud from the wall painting first, to allow the restorers to see where they were going to drill the holes needed for the injections. The consolidation process followed the same procedure performed in the first story.

So

the

cleaning

was

divided

in

two

stages.

The

first

one,

the

removal

of

the

mud

coating,

was

carried

out

using

surgical

knives

and

sharpened

spatulas.

Since

the

coating

was

too

hard

to

be

worked

on,

compresses

of

cotton

soaked

in

a

surfactant

solution

were

applied

on

the

surface

to

be

cleaned

for

a

period

of

4

hours.

After

the

removal

of

the

compress,

an

hour

was

needed

before

any

action

be

taken

because

the

softened

paint

layer

could

have

been

removed

together

with

the

mud.

In

this

way

the

paint

layer

could

dry

sufficiently

and

the

removal

of

the

mud

was

possible

without

any

harm

for

the

painting.

The

second

stage

consisted

in

removing

the

darkened

varnish

with

chemicals.

The

cleaning

was

carried

out

through

Japanese

tissue

paper

by

absorption

of

the

swollen

varnish

into

the

tissue

and

the

cotton

swab.

A

solution

of

two

different

formulas

of

EDTA

in

water

were

used

for

that

purpose:

wet

Japanese

tissue

paper

was

applied

to

the

paint

layer

to

avoid

that

accidental

abrasion

of

the

cotton

swabs,

soaked

in

the

solution,

could

harm

the

paintings.

The

use

of

EDTA

solutions

was

followed

by

the

use

of

a

weak

solution

of

Arabic

gum

to

refine

the

cleaning.

The

tissue

paper

was

removed

only

after

the

cleaning

was

finished

and

a

new

tissue

paper

was

applied

in

order

to

remove

any

possible

deposit

of

the

salt

through

the

use

of

distilled

water.

The

upper

section

of

the

wall

paintings

didn’t

have

the

coating

of

mud

probably

because

it

was

already

blackened

when

the

application

of

the

mud

took

place.

This

cleaning

was

performed

with

the

use

of

organic

chemicals,

applied

directly

on

the

thick

deposits

of

soot

and

grime.

Wooden

ceiling:
Three mandalas were present on the ceiling of the second story: they looked contemporaneous to the murals. They were painted on square panels made out of different wooden planks. After the mandalas were removed from the ceiling it was noticed that some of the planks did not adhere properly and they might have separated. It was decided to glue the planks after the cleaning because the chemical used for that purpose could have melt the binder used for fixing the planks. All mandalas were cleaned off the varnish and the soot deposits employing cotton swabs soaked in organic chemicals. Soon after, the planks were glued with a PVA binder and they were protected with a 3% solution of Paraloid B72.

Plastering:

cracks, fissures and holes were plastered up to the level of paint layer with a local clay mixed with a PVA binder. The surface had to be previously wet with 10% PVA solution in water in order to enhance the adhesive power of the plaster.

Retouching:

a sample of retouching was carried out on a small section on the eastern side of south wall. Watercolors were used to match abraded or missing colours with the original paint layer.