Casting using the lost wax method – every image is unique.

Bronzes produced using the lost wax method are unique, individually hand crafted by master sculptures using ancient techniques and driven by Buddhist religious ideology and merit, carved and sculptured for religious purposes a highly innovative process requiring great skill, experience and patience as outlined in the copy below:

1. First a core is made in the rough shape of the completed image – made from a mixture of clay, sand and rice husks, rice husks prevent the clay from cracking and shrinking while it dries.

2. Once the core is formed its left to dry in the sun for several days. Sheets of bees wax are rolled flat and warmed to become pliable, then shaped over the core. The thickness of this wax will determine the thickness of the finished metal.

3. The wax is then sculptured to form every minute detail including the facial features, decorative patterns and clothing, any mark on the wax will be transferred to the cast metal. Pieces of pre-formed wax are applied to the body such as the hair curls, ears, fingers and any decorative jewellery.

4. Nail like pins are pushed through the wax into the core to hold the core in place while the wax is melted out, and the metal pored in. After casing the pins are removed and the holes filled with bronze or silver plugs. The next step is to cover the wax image with an outer investment The first layers applied are finely ground – so as to keep all the detail in the wax. This outer investment consists of clay mixed with cow dung and water. The dung prevents it from cracking during drying. More and more layers are applied each one allowed to dry first. Unlike the core this outer investment is dried slowly in the shade to prevent any cracking as this would show in the final bronze image. Once the fine layers have been applied increasingly courser layers are applied consisting of clay and sand. At this point a wire web would be wrapped around the whole investment to add support.

A religious ceremony accompanied by monks would mark the casting of larger images. The investment is placed over the fireplace to allow the heat to melt the wax away into holding pans for re-use. Leaving an empty cavity between the core and the outer investment supported by the metal pins. The investment is fired, turned upside down and the molten copper alloy poured in. Once the metal has cooled the outer investment is broken open with a hammer to reveal the image, the surface is then filed and worked smooth.

Introduction to the history and classification
of Thai bronze Buddha images.

Below is a consise outline compiled by 'Gandhara' showing the subtle differences in bronze, patina and artistic styles of Thai sculpture, some of which can be applied to the classification of images from Laos, Burma and Cambodia:

Thai Bronzes

Green or blue patina indicates copper carbonates. Red patina indicates copper oxide. Alloys high in tin content (>15%) are silvery in colour, however a high tin content also produces a very brittle metal, low tin alloys (<5%) are a warm copper brown colour.

Finely cast images with smooth surface and deep coloured patina e.g. a deep emerald green, is found in a number of northern Thai/Lao images. This is due to the arsenic content of the bronze alloy used, a deliberate combination of copper, arsenic (>1%), tin and lead which produce a fine smooth surface corrosion during burial. The arsenic content acts as a corrosion inhibitor. Images like this can possibly be connected with one Lan Na ore source. Red pigment found in the recesses of many images is probably cinnabar pigment.

Daravati/Lopburi 9-12thC

Some of these images the hair is formed by scoring horizontal & vertical lines, forming square like notches. Some late Lopburi images of the second half of the 14thC have a vertical cleft extending from the upper lip below the nose through to the chin. This was replaced in the late 14thC early 15thC (Sukhothai period) with a ‘U’ shaped incision on the chin.

Sukhothai 13-15thC

Sukhothai bronze mix has negligible zinc and more lead content than tin. Hair curls made of ‘wax worms’ and cast solid. Characteristics – ‘U’ shaped incision on the chin, ‘S’ shaped eyes with an incised line separating the lid from the brow.

The robe edge from left wrist to left knee has three scalloped sections, this was later carried forward to some Lan Na images (Shining types). Pedestals with a narrow band, small feet and end within the knee, belong to the early period (late 14thC) later pedestals are broader and end outside the knee.

Later period images, 15thC, the flame radiance was attached the usnisa after casting separately, on earlier images the radiance was always cast integrally with the image. Some Sukhothai images retain a Khmer influence as do early Ayutthaya images. For example the decorated sampot and armlets.

U-Tong 14-15thC

U-tong facial modelling relates back to 13thC Lopburi. The radiance developed into a spike or elongated gem rather than a flame. Upper edges of the eyes are straight. All sculptural detail is carved in the wax state not applied as separate pieces (as in Sukhothai), that includes the smooth bump-like curls, which were formed by pressing a concave dome shaped tool into the wax.

Lan Na

Images of the late 15thC and early 16thC belong primerally to two modes, one is the Shining or Chiengsen the other is the 'standard' Thai type with long mantel, right hand on the shin, folded legs and generally a flame radiance. These images have a connection with Sukhothai images – in the nature of the curves of the face and lips.

Characteristics of Lan Na/Chiengsen are rounded face more shallowly modelled than most Sukhothai images, a swelling chest and broad shoulders and a pedestal generally broader than the knees with no feet. The Shining or Chiengsen images date from the mid 15thC (1441-87).

The lotus petal pedestal (8thC Indian origins) is thought to begin to appear about the same time as the Shining type, second half of the 15thC (however a lotus petal pedestal appears on a Thai stele dated 1514). The angled cornered plinth pedestal thought to have arrived from lower Burma in the 15thC or possibly earlier.

On late 15thC Lan Na images, the sash mantel is short. Non Shining images – legs lie on top of one another, the right hand rests left of the knee, the mantel is long and the radiance in the form of a flame. Lan Na lasted until the first few decades of the 16thC during this later period the Crowned Lan Na Buddha was introduced. The Crowned Buddha or Buddha in royal attire – prominent in the 12th & 13thC but absent in Sukhothai and early Ayutthaya periods.

Lan Sang or Lan Chang images from Laos and Northern Thailand – dated images of this class range from 1682-1701. Characteristics are lifted brows, mouth brought forward and incised decorative lines - especially on the ears.

Nakhon Si Thammarat 14-15thC

Nakhon Si Thammarat images are of a Shining type, having spreading pedestals (lower part of the pedestal flares out) and an indication of robe folds between the ankles/legs incised into the pedestal. Decorative detailing on the base similar to the Bangkok period would point to a much later date – late 17 or 18thC.

15-17thC – the robe edge runs from the mantel to the waist, shorter mantel is usually associated with later images.

Ayutthaya

Later Ayutthaya images can be divided into three periods – 16th,17th and 18thC, 1491-1569-1688-1767. Many Early Ayutthaya images are very closely related to the Shining type;
with gem radiance; the hand on the knee; short mantel and seated in vajrasana (both feet facing up).

Early Ayutthaya images 14-15thC the curls were stamped in rows using a dome shaped tool and the pedestal is of the early standard Ayutthaya 3 part type. The flaring/tiered pedestal is a 16thC development. A double forehead band with striated lower edge – is an established characteristic of the early Ayutthaya type.

Some 16thC images are found to have a square base, some depicting statues of the vanquished army of Mara. This was a new element introduced during the Ayutthaya period. 16thC and later images have a gem 'cone' shaped radiance rather than a flame, a short mantle, ending above the right nipple, the right hand upon the knee rather than inside it, legs folded in ‘vajrasana’ (both feet facing up). Robe corners are depicted upon the pedestal between the legs. The pedestal is broader than the knees rather than narrower and on some examples a robe end is wrapped around the left wrist.

Both Ayutthaya and Sukhothai images have an incised line separating the lid from the brow but the modelling of the Ayutthaya eyes and eyebrows are much shallower.

Crowned Buddha images rare in the 15thC but popular in the 16thC. The typical Ayutthaya crowned image with such features as a headdress of tiered rings - appears to have become established at the end of the 15th or early 16thC. Seated Crowned Buddha images were rare in the mid 16thC and standing crowned images were common during this period. However in the early 17thC seated crowned images took primary position. At their apogee (second half of the 17thC) the crowned images are heavily adorned, trapped inside a flickering web of gems.

Burmese

An image wearing a large crown and jewelled robes is typical of the Jambupatti images in the Shan States, this is the only place where this particular type appears. It stems from when Sakyamuni converted the heretic king Jambupatti by appearing in royal attire.

Khmer

Khmer Art is arguably the most sought after and respected art of south east Asia. From early 6th century to 14th century the sculpture developed into a unique and stylish form
of Art developed and based on Indian iconography and sacred beliefs, following exclusively religious objectives. It is based on indigenous notions of belief as well as those incorporated into Southeast Asian culture with strong Indian influence. Inevitably, Indian culture has great influence on Khmer work of arts. Shivaism, Vishnuism and Saktiism had been the model for most of Khmer artifacts and stone sculptures.

Bapuon style images oftain wear a necklace with large pendants
Kon Ker – pre Angkor capital 9-10C. This style wears no jewellery and the pleats on the sampot are very wide.
Bapuon 11thC – has an incised lines for eyes and moustache, the legs are represented close together.
Bayon style 12thC – wears jewellery, necklace and bracelets and the legs of the image are further apart than in Bapuon style.

Styles AD
Kulen 827-877
Preah Ko 877-897
Bakheng 897-927
Koh Ker 922-947
Pre Rup 947-967
Bahteay Srei 967-1007
Khleang 967-1017
Baphuon 1017-1087
Angkor Wat 1107-1177
Bayon 1177-1237

Forward to: Table of Thai and Khmer sculpture

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Introduction to the history and classification of Thai bronze Buddha images.

Thai Bronzes

Daravati/Lopburi
9-12thC

Sukhothai 13-15thC

U-Tong 14-15thC

Lan Na

Nakhon Si Thammarat 14-15thC

Ayutthaya

Burmese

Khmer