By Walter Eigner*
Dating Thai Coins
Thai coins use a unique dating system which may at first seem somewhat confusing. They almost always bear their dates using Thai numerals and use three different year numbering systems. To translate a Thai year to an Anno Domini year numbering system, first translate the numerals to Arabic numerals.
A chart comparing Thai numerals to Arabic Numerals
Depending on the era during which the coin was struck, the numerals may reflect a year represented in one of three year numbering systems:
Chula-Sakarat (จุลศักราช)
The Chula-Sakarat system, often abbreviated as C.S. is a year numbering system that begins in the year 639 A.D. Therefore, to convert a C.S. year to an A.D. year, simply add 639 to the year or 638 if the date falls before the middle of April (as the Buddhist New Year starts in April). The origins of the system is unknown but it saw wide use in the Lanna, Sukhothai and Ayutthaya kingdoms and it was thought to originate from the Buddhist patriarch Buppasoranhan, who seized the Burmese throne in 639 A.D.
2 Att coin from the reign of King Rama V1
This coin bears the year จ.ศ. ๑๒๓๘ which translates to C.S. 1238. By adding 638 to this year we get the year 1876 which puts this in the second year of production for the issue. To convert this year to the Buddhist system, the year numbering system currently used in Thailand and what you will commonly find in Thai catalogues, simply add 543 to the A.D. year to get the year B.E. 2419.
Rattanakosin Sok (รัตนโกสินทรศก)
Rattanakosin Sok, abbreviated R.S. was the year numbering system introduced by King Chulalongkorn and predominantly used from 1890 to 1912 which sets the first year at 1782 A.D, the year of the ascension of Chao Pharaya Chakri to King Buddha Yodfa Chulalok, the founder of the Chakri Dynasty and the founder of Rattanakosin (Bangkok) as the capital. Therefore, to translate R.S. years to A.D. years, add 1781 to the year.
1 baht coin from the reign of King Rama V2
This 1 baht coin bears the year ร.ศ. ๑๒๗ which translates to R.S. 127. By adding 1781 to this year we get the year 1908 A.D. or B.E. 2451. This sets it as one of the last years in the reign of King Chulalongkorn, although these coins did not see distribution until after his death in 1910.
Buddhist Era (พุทธศักราช)
The year numbering system currently used in Thailand is known as the Buddhist Era, abbreviated to B.E. This year numbering system was introduced in 1910 by King Vajiravudh and starts at the year 544 BC, the year of the death of Buddha. Thus, to convert a Buddhist year to an Anno Domini year, simply subtract 543.
The year numbering system currently used in Thailand is known as the Buddhist Era,
abbreviated to B.E.
When reading the denomination, often the word neung (หนึ่ง), meaning one, will appear before or after the denomination. In addition, 10 will often be written as sib (สิบ).
A 1 Salung coin from the reign of King Rama V
From this coin, we can see the denomination around the base สลึงหนึ่ง (salung neung) equaling one quarter baht or two fuang.
2 Att coin from the reign of King Rama V1
This coin bears the wording เสี้ยว ๔ อันเฟื้อง (siaw 4 an fuang), or one quarter fuang. This coin equals 1/32 baht and is often referred to as a 2 Att coin.
This coin bears the text หนึ่งบาท (neung baht)
This coin bears the text หนึ่งบาท (neung baht) in the lower legend meaning 1 baht so we can identify this as a 1 baht coin.
References:
*Walter Eigner, Australian University Internship student
1. Heritage Auctions - 2006 January (HWCA) New York Signature Auction - http://coins.ha.com/c/item.zx?saleNo=397&lotNo=14697
2. Heritage Auctions - 2007 January New York Signature World Coin Auction - http://coins.ha.com/c/item.zx?saleNo=425&lotNo=53050
3. iCollector - Coin Kingdom, LLC Auction - http://www.icollector.com/Thailand-King-Rama-VI-AR-1-Baht-1914-Choice-VF-XF-Key-fate_i11448054
