Limbu Sign Sa-I

It cancels the built-in vowel on a final Limbu consonant.

Some Limbu consonants have a small ending form; when one is unavailable, ᤻ follows the full consonant. The Limbu virama-like sign is based on the Indic virama, a mark that cancels the vowel built into a consonant.

A British Library catalog labels a Limbu alphabet book “early 18th century (?)” and dates accompanying Nepali notes to “c.1730 or earlier.” A Unicode proposal describes the oldest known Limbu writings as collected in the “1850s” and says the modern script began developing in “1925.” Those dates describe the wider script record, not this sign's first appearance.

Why does Limbu sa-i differ between Nepal and Sikkim?

Sikkim can use it for vowel length; Nepal usually uses kemphreng.

In Sikkim-style Limbu spelling, sa-i can cancel the final consonant's built-in vowel and mark the preceding vowel as long. Nepal-style spelling usually puts the length mark on kemphreng and reserves sa-i for finals without a small ending form.

The Srijanga script developed and spread in Kalimpong, Darjeeling, and Sikkim “from the 1920s” for teaching, literature, and ritual transmission. Limbu mundhum publications—works of ritual and oral tradition—appeared in the script especially “after 1990.”