Boly… from the Sea to Siam Currency
Boly… from the Sea to Siam Currency
2/9/2561 / 129 / สร้างโดย Web Admin

During an ancient era, the boly was used as a means of community trading. It was popularly used among communities around various areas of the ancient Caribbean lakes, American coastal lines, Indo-pacific and Africa which are on the Arab sea line trading routes. It was discovered that the duration of boly trading was over 4000 years ago.

The boly is a seashell of a single valve in a species of cypraeidea. Its outer shell was thick with a curved transparent upper part while the lower part was flat with wavy lines. The skin was oily with many different colours found from its more than 200 species. Boly are mainly found in warm water coastal areas, especially around the Indian ocean but mostly commonly in the Maldives, and around the west and northwest pacific ocean. Moreover, there is evidence that, while on his sea trip during the 14th Buddhist Era, King Sulaiman noted that; In the Maldives, a boly was the only currency used. When the royal treasury ran out, the queen would order her women to throw coconut branches into the sea to become new habitats for the shell, and later, the women could pick them once the branches were placed on land by the sea waves. The treasury storehouse would then be filled again with the boly. There is also a record of Pyrard de Laval, a French Sea Explorer, who had spent 2 years in the Maldives and wrote that; They called the single valve shell boly and it was exported everywhere. In one year, there were 30 to 40 ships containing only boly sent to Bengal. They were of high value and the Bengali also used them as currency, despite the fact that they had silver, gold and other valuable metals. Most interestingly, the King and his councils built a special storehouse to keep only the boly and treated them as one of the most valuable items. On the other hand, Portuguese ships would carry rice from Cochin to exchange for boly in Bengal Markets where the venders would put 12,000 boly shells in a coconut basket for exchanging. The profit could be 3 to 4 times the cost. As for the boly collecting period, it was noted that an entire coconut tree would be placed in the sea where the boly could use the branches as a habitat. After 4 to 5 months, the tree would be pulled back to the land and the boly picked and placed in sand or land holes for about a year for the shell meat to deteriorate, once clean the shells were then ready for trading.

Picture1: From the Sea to Siam Currency

Picture1: From the Sea to Siam Currency


Roles of Boly in Siam Country

Presumably, the route that brought the boly to Southeast Asia and the neighbouring regions was via the warm seawater coastal lines, Indian Ocean or the Philippines. The information recorded by Marco Polo, an Italian merchant and explorer from Venice, stated the use of boly from India in Yunnan Territory during 18-22th Buddhist Era was used for trading and exchanging of goods in the area. This also included Siam (Thailand). However, archeological evidence shows us that the boly was used since pre-history. The use of boly was more than a medium of exchange, it was also used for a decoration, as sacred item or other beliefs. For instance, at Banmai Chaimonkon Heritage Site, Nakornsawan Province and Ban Takhae Heritage Site, Lopburi Province, the display of the boly is in a form of an ornament and a wreath donated after death. There are traces of 2-3 pieces of the shell being cut, smoothed before being placed next to the corpse. While at Pong Manao Heritage Site, Lopburi Province, the boly was cut in half and smoothed into a straight line. Nevertheless, it is not conclusive whether the boly was used as a means of exchange or an ornament but one could say that, during the pre-history of Siam, the boly was a rare item that they were found from a salt water source. This also represented that Siam had a connection with the outside communities or communities along the seawater coastal lines.

Somdej Gromphraya Dumrongrajanuparp noted in his book called the Legend of Currency on the use of boly (or bia in Thai) as a currency in Siam that; In Siam, silver and boly (bia) were used as a trading exchange since the Sukhothai era. The silver was an imported metal and melted down for the making of coins in the country whereas the boly was brought in by foreigners travelling from coastal areas and sold to the locals to be used as a trading medium. This trading style was carried on throughout the Ayudhaya era.

During the Sukhothai era, evidence has been revealed on stone inscriptions that states; The regime of Phor Khun Ramkamhang, Muang Sukhothai, was good as there were fish in water and rice in rice fields; leaders did not collect taxes; people sold cows; people sold horses; people could trade whatever they wanted; people were happy. This statement shows that even though there were free trade activities in the territory leaders did not collect taxes on animals or goods that were being traded. People were free to trade any goods, including silver or gold. This also demonstrates that silver and gold were either used as goods or as an exchanging medium or both. Moreover, evidence also shows that people of the sukhothai era preferred to use bia as an exchanging medium mostly in a form of coins for every day uses and silver or gold for more valuable items. The boly that was brought in from the Maldives in the Indian ocean came in different sizes, yet of same cost. Names for the Boly were varied such as Bia, Plong, Bia-kae, Bia-jan, Bia-nang, Bia-ponglom or Bia-bua. The exchange rate was 800 bia for 1 Fueng Coin. Bia was additionally found in religious areas as seen on the stone inscription during Phor Khun Ramkamhang reign stating that; At Khatin (religious) ceremonies, there were bia, betel nuts, flowers, mats for sitting and lying on, ornaments and giving away coins. Whereas on the Wat Pa-mamuang’s stone inscription, presumably built during Phaya Lithai Regime, it states that; The royal donation items included ten thousand gold, ten million bia, two million betel nuts and 400 saffron robes. All of these statements represent evidence of the King’s merit making on religious performances and that the bia was playing a role of currency.

Later, during ayudhya era, the boly was widely popular with the exchange rate of 800-900 bia for 1 fueng coin, depending on the number brought into the country. The favourite bia was bia-jan and bia-nang. The evidence of Mha Juan, a chinese noble and sea explorer, noted the information about the Kingdom of Siam during 1433 (B.E. 1976) or around the regime of King Phra Boromrajatirat II (Chao Samphraya) that there was use of boly from the Maldives as a currency through out the kingdom with various choices to use gold, silver or copper. Similar to the Sukhothai period, the popular boly was mostly brought in from the Maldives though there were a few from the Philippines. Mr. La Lube’s annals noted that; using bia as a small currency in Siam. The currency of the lowest cost used in Siam was that of a small shell, which I have mentioned and illustrated its size earlier.The Europeans residing in this country called it gori, the Siamese called it bia. The bia could be found in plentiful supply in the Maldives, but sometimes a few came from the Philippines. Navarat stated in his book, the Speech on China, page 61 about this gori, which he pronounced Sigueies, that; The bia was brought in from along the Indian Coast and also from Manila, mostly from Luban, a small Island in the Philippines. He later noted that; Sigueies were from Baidivia Island (which, in fact, was the same as the Maldives).

Moreover, during the ayudhaya era, apart from using the boly as an exchange currency, there is evidence that it was used in many other occasions. For example, it was used in the measurement ratio as illustrated in Mr. La Lube’s annals that; Siamese people used tanan as a unit of measuring rice and liqueur. They also used a coconut bowl or tanan as a unit of measuring grains and drinks. Since the coconut bowls were varied in sizes, they used goris to test the content of tanan. The goris being used as small currency in Siam were not much different in size and it is said that some tanans could contain up to one thousand bias while others may be able to take only five hundred bias.

In regards to the social aspect, during ayudhaya era, the governing group used the bia as a legal designated fee to control people, especially people of the lower classes such as labourers or slaves. This was stated in many acts of Tra Samduang Law, for example on the character of theft, as follows; 116 act 1 – if a person takes a valuable item from a trader without paying for it, the person must be arrested and taken to the authorities to be punished. If the item is worth about 500 bias, the person must be fined, hung and the body be carried around the market for 3 days to ensure the action is not copied.

121 act 1, if a person is found stealing one to ten bunches of betel nuts, the person must be fined 3 bunches, each bunch worth 25,000 bias. If a person steals one bunch of coconut, the person must be fined 15,000 bias and if a person steals one bunch of bananas, the fine will be 15,000 bias.

123 act 1, if a person burns something on his/her land and the burning extends to others’ land, the person must pay a fine of 555,000 bias per rai of land.

Apart from the economic and social roles during the ayudhaya period, it was also found that bia had an important role in some religious aspects and beliefs. For instance, the discovery of 256 bolies around an old piling in the western area of pagoda number 2 while digging around the temple, Wat Kae-rye; more than 10 bia-jans were found around a lead coffin with gold seal in the temple, Wat Phra Srisanpet. The legend of the old capital noted that; One may say that all royal gravestones in Wat Phra Srisanpet contain royal remains. Many years ago, one small royal gravestone was found at the west side of the temple with the stone broken down to its foundation. Upon further digging, a lead coffin with a gold seal containing the small remains of a body was found, which presumably belongs to a young royal who passed away at the early age. In the coffin, there were more than 10 bia-jans.

Furthermore, during the reign of King Boromkote, information in the royal fortune teller’s annals says that; The year of the rat, 2287 (1744) on Friday 6th in the 12th month of the Thai lunar calendar there was a fire burning in front of the palace where ceramic coins were used instead of bias. This evidence shows the insufficient amount of bias being used as a common currency that they had to produce the ceramic coins as a replacement. However, the coins were only used for a temporary period, once the boly were brought in, bias were back in use again.


Picture2: This evidence shows the insufficient amount of bias being used as a common currency that they had to produce the ceramic coins as a replacement.

Picture2: This evidence shows the insufficient amount of bias being used as a common currency that they had to produce the ceramic coins as a replacement.

It can be summarized that during the ayudhaya era, boly was applicable in many aspects, especially in the economic aspect as it was used as a common form of currency for trading goods. Although other metals could be produced as coins, the boly was still more mutually reliable and acceptable among traders. As for the social aspect, the boly was designated as legal tender and was stated in law enforcement of society, especially with the lower classed citizen, labourers or slaves. In terms of religion, the boly was tied to some beliefs. Nevertheless, one of the biggest reasons why the boly was used as a common currency was the fact that boly was obtained from a natural source that no one could fake.

Later, during thr thonburi era, the boly was still used as a common currency together with pod-duang coins. A war during this reign caused an increment of the exchange rate to be 200 bia per fuang (1,600 bias per baht) which was too extreme for the country’s economic situation where people lived on 3-4 bias per day.

During the Ratanakosin Dynasty of King Rama I, bia and a pod-duang coins were continuously used. However, the fixed exchange rate was set as 400 bias per fuang and punishment was issued in case violation occurred. During the reign of King Rama III, the country’s economy significantly improved with more trading, so a great deal of bolies were brought into the country resulting in a situation of inflation. The exchange rate became 1,300 bia per fuang (10,400 bias per baht). There was also another significant factor about the currency being the King declared the discontinuation of the use of the boly. It was because he considered that a boly was a sea animal that it was not only sinful but also abusive to use. Subsequently, King Rama III graciously assigned Chao Phraya Klang–Dit (Finance Minister) to seek an alternative after becoming aware that some coastal cities such as Singapore were using a round-flat metal coin like some European countries. Chao Phraya Klang consulted with Mr. Robert Hunter and asked him to produce a metal coin using a sample of an English coin. The new coin, replacing boly, was called Rhien Muang Thai and was produced in 2 styles (1) one side of the coin has an emblem of a lotus flower, and (2) an emblem of an elephant. The King was not impressed with these coins so he ordered the stopping of production. During the next period of King Rama IV, Siam made an international trade agreement leadtrader the country needing to have a lot more money because not only were the pod-duang coin in insufficient supply there were a number of fraudulent pod-duang coins in circulation. The boly by then had become almost worthless as the saying goes; 100 bias is not even enough for a meal. Moreover, a minting machine that was brought in from England had started producing a round-flat coin. The boly was gradually used less and less and eventually became eliminated.

Picture3: From the Sea to Siam CurrencyThe new coin, replacing boly, was called Rhien Muang Thai

Picture3: From the Sea to Siam CurrencyThe new coin, replacing boly, was called Rhien Muang Thai

It can be said that in the Kingdom of Siam, a boly was used in an ancient community for a long period of time, since pre-history, although it is not conclusive that it was used as a means to replace the currency. The evidence of Siam history shows that whether the boly was used as a medium for trading or as a currency, it continuously existed from the reign of Sukhothai, Ayudhaya, Thonburi onto early Ratanakosin era. Most of the boly was brought in from the Maldives in the Indian Ocean which shows that there was a long trading relationship between Siam and other coastal cities. The value of the boly fluctuated based on the amount brought in by the merchants that traded during King Rama IV reign and when the minting machine was brought in and was capable of producing a great deal of metal coins the the exchange rate of boly became less when being compared with the newly produced coins. Subsequently, the use of the boly/bia in society was gradually decreased and finally stopped in the reign of King Rama IV of Siam.     

Today, a display of the boly is held at Display Number 9, Thai Currency Evolution, at the Pavilion of the Regalia, Royal Decorations and Coins. The display demonstrates various types of coins from the past to the present. The hall is open daily for the public during 08.30-16.00 (except the days of the royal duties).

Translated from
Nattakarn Jantayod. (2014). Boly… from the Sea to Siam Currency. (Thai version) Retrieved September 14, 2014, from Pavilion of Regalia, Royal Decorations and Coins e-museum: http://emuseum.treasury.go.th


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