The use of mother-of-pearl to adorn various objects has a long history in Thailand. Stucco pieces studded with bits of shell have been found at monuments dating back to the Dvaravati period (6th to 11th centuries), and some form of the art may have existed even before along the coastal regions.

But these early efforts were crude compared with the magnificent works achieved by techniques perfected in the late Ayutthaya and early Bangkok periods, when temple doors and windows, manuscript boxes, alms bowls, and numerous other items were splendidly decorated by the painstaking process the Thais call krueng mook. The craft continues to thrive today in the production of exquistely detailed furniture, mirror frames, boxes, and trays that are the pride of many owners both in Thailand and abroad.

Many seashells fall into the general category of mother-of-pearl, but the most popular in Thailand is the hoi fai, or flame snail, from the Gulf of Thailand, which has a particularly beautiful irridescence. The outer surface of this shell is removed with a special knife and the white inner shell is cut into thin, fairly flat pieces, each about two and a half centimeters long.

The pieces are honed until smooth and shiny and then usually glued onto smooth, flat pieces of thin wood. The design,. if simple, is traced directly onto the shell surface; for more complex ones, tracing paper with the pattern drawn on it is glued to the shell. A special curved bow saw is used to cut the mother-of-pearl, after which it is carefully removed from the wood and the cut edges smoothed with a hand file to ensure that they will fit tightly together.

If the design was sketched directly onto the shell, the pieces are pasted in their proper places on the tracing paper, which is then pressed, paper side up, on the sticky, newly lacquered surface of the item being decorated. After the paper has been moistened and peeled off, the surface is rubbed with a hard stone to restore its shine and defective patches repaired with more lacquer; there is then another polishing and a final coat of clear varnish.

The highest quality mother-of-pearl work requires both time and an amazing amount of patience. Evidence of this can been seen in the doors and windows of the chapel at Bangkok's Wat Ratchabophit, on which one square metre contains approximately 20,000 tiny pieces of shell.