like the pound, originated from a traditional unit of mass.Its currency value was originally expressed as that of silver of corresponding weight (now defined as 15 grams), and was in use probably as early as the Sukhothai period in the form of bullet coins known in Thai as phot duang (Thai: ).Cowrie shells from the Mekong River had been used as currency for small amounts since the Sukhothai period.Before 1860, Thailand did not produce coins using modern methods.Instead, a so-called "bullet" coinage was used, consisting of bars of metal, thicker in the middle, bent round to form a complete circle on which identifying marks were stamped., 2, and 4 baht in gold. Between 18, foreign trade coins were also stamped by the government for use in Thailand. These were silver 1 sik, 1 fuang, 1 and 2 salung, 1, 2, and 4 baht, with the baht weighing 15.244 grams and the others weight related.Tin 1 solot and 1 att followed in 1862, with gold , 4, and 8 baht introduced in 1863 and copper 2 and 4 att in 1865.The mint is considering expanding the use of multi-ply plated steel technology to other coin denominations due to volatile base metal prices and rising production costs.
This translates into savings in time and materials for the mint.Before 1880 the exchange rate was fixed at eight baht per pound sterling, falling to 10 to the pound during the 1880s.In 1902, the government began to increase the value of the baht by following all increases in the value of silver against gold but not reducing it when the silver price fell.Beginning at 21.75 baht = one pound sterling, the currency rose in value until, in 1908, a fixed peg to the British pound sterling was established of 13 baht = one pound.This was revised to 12 baht in 1919 and then, after a period of instability, to 11 baht in 1923.
The old design will not be removed from circulation.