Chhertum Coin: Bhutanese Fractional Currency

Illustrated Specimen Details: 25 Chhertum

Example Specimen: 25 chhertum, 1979 (Kingdom of Bhutan)

Design & Symbols: The coin is rich in Vajrayana Buddhist symbolism, the state religion of Bhutan. The obverse features the denomination TWENTY FIVE CHHERTUM (with the Dzongkha script ཕྱེད་ཀྲམ་ཉརེ་ལྔ།) and the Tibetan vishvavajra — two crossing vajras (a legendary ritual weapon, also known as a dorje or double diamond-thunderbolt). This symbol, also present on the state emblem, represents harmony between secular and religious power. The reverse displays the inscription ROYAL GOVERNMENT OF BHUTAN alongside two golden fishes (gaurmatsya), representing the auspiciousness of all sentient beings.

Numismatic Note: It is interesting that initially in 1979, a copper-nickel alloy coin of this type was issued. However, later, until 2003, the exact same coin was produced from a different alloy — aluminum-bronze plated steel. The Royal Mint decided to keep the date "1979". It is easy to distinguish the later emissions, as they respond to a magnet.

1. KINGDOM OF BHUTAN (PRE-DECIMAL): 1 rupee ≈ 32 chhertum.

History and Etymology of the Chhertum

The chhertum is a fractional coin denomination of the Himalayan kingdom of Bhutan. Its history bridges two distinct economic eras: it began as a traditional minor unit tied to the Indian trade economy and was later formalized into a decimal subdivision.

Origins and the Cooch Behar Connection

The term "chhertum" is derived from regional linguistic roots and literally translates as "half of the coin". Historically, this term specifically designated half of a 1 rupee coin from the neighboring Indian principality of Cooch Behar (Koch Bihar). This reflects Bhutan’s long-standing economic connection with the Indian subcontinent, where the rupee served as a reference unit in trade. Before full decimalization, the relationship in the historical Bhutanese system was generally 1 rupee ≈ 32 chhertum.

Decimalization and Spelling Changes

In 1974, Bhutan reformed its currency system and introduced the ngultrum, aligning it with the Indian rupee on a decimal basis. The fractional unit was retained, where 1 ngultrum = 100 chhertum (or chetrum). This preserved the historical name while fundamentally changing its monetary context.

Regarding the name of the coin (Dzongkha "ཕྱེད་ཏམ"), both "chhertum" and "chetrum" are Latinized spellings of the same word. It remains unknown why the official English spelling was changed to chhertum specifically for the 1979 emissions, but both terms denote the exact same fractional value.

Numismatic Perspective

Physically, historical pre-decimal chhertum coins were often struck in copper or bronze using traditional methods, resulting in varying strike qualities. Modern decimal issues, like the 1979 series minted in the UK, feature clean, standardized geometric layouts that beautifully incorporate Bhutanese cultural and religious motifs.