Notes on Techniques
Metal has been the preferred material of Himalayan sculptors for centuries. The two primary techniques are lost wax casting and repoussé.
Lost Wax Casting
Most of the smaller statues are cast using the lost wax technique. The figure is initially sculpted in wax and then carefully covered with layers of clay. Molten metal is poured in through channels to the interior of the mould, which takes the place of the wax that melts and flows out through vent holes. The different elements of a statue—the stand, pedestal, figures, arms and heads—are usually made separately and fastened together with metal clasps, dovetails or rivets.
Works that are cast or created through repoussé are finished with a chisel, including the ornamental details of the clothing and plinths, as well as any facial expressions.
A cavity is ‘hollowed out’ in the metal with a chisel. The carefully cut inlays of metals or precious stones are then hammered into the parent metal. Turquoise and ruby are popular among Tibetan artisans.
Many statues are gilded. An early method of gilding consisted of using a brush to apply gold mixed with resin or honey. Gilding with mercury, or fire-gilding, was later introduced to Nepal and Tibet around the 10th century. This is also known as amalgamated gilding, which involves mixing gold into a mercury solution and then placing the gold onto metal surfaces after the mercury evaporates. In Tibet and Mongolia, some metallic statues are completely painted, though generally just the face and hair are highlighted with paint.
Thangkas are religious images painted on textiles with water-soluble pigments made from ground minerals, including gold and plants mixed with a glue solution. Before and during the painting process, the artist will sometimes chant specific mantras, as well as the painting instructions.
After completion of the statue or thangka, it is consecrated with a ritual blessing by a person of high spiritual quality who invites the deity to inhabit the completed work. In some statues, sacred objects are installed within and then the base is sealed. The covering metal sheets are usually chased with an icon of crossed-vajras, symbolising the immovable state of Buddha’s enlightenment, and to fend off evil forces. For thangkas, sometimes a blessing will also include the writing of special mantras, or a high lama’s handprints on the back.