The Tibetan Srang is a unit that originally corresponded to the weight of about 37 grams of silver. 6 2/3 Tam corresponded to 1 Srang.
Notes of the Srang system were made by pasting together three sheets of paper, the middle one having a two-line security legend printed on it and they were many varieties in size, printing and color. Direct reading of security text is accomplished when the face is held up to a light source.
Tibetan banknotes were first issued in January 1913 with the denomination of 5 [green or blue] and 10 tam [red].All notes have the following characteristics in common:
The early Tibetan notes were woodblock printed on locally-produced paper and were hand-numbered with black ink.
For this purpose, young people were specially trained in calligraphy. Since the young men mostly came from the province "E", the calligraphers were called 'e-ba' or 'i-drug-pa'. The young copyists received their training in an office called 'e-khang' located within the Potala and learned how to write government documents in a calligraphically correct manner. For individuals who did not receive this specialized training, it was nearly impossible to accurately imitate the written numerals on the notes. Therefore, counterfeit notes can often be identified at first glance by the amateurish spelling of the serial numbers.
The multicolored 50 Tam and the later 5 and 10 Srang notes have a double perforation on the right edge. With the help of this device, the notes could be bundled into 10 or 20 pieces each.
The Paper was produced by Chin-Tung Paper Factory near Lhasa, containing root of poisonous weed in order to prevent the spoiling by insects and rats.
In 1959, the Chinese occupiers declared the Tibetan paper money invalid, withdrew it from circulation and replaced it with Chinese money. Today, these notes have become sought-after items by international collectors.