North Indic quarter mark

It helps separate the intended reading from other possible readings.

The fraction signs ꠰, ꠱ and ꠲ mean one-quarter, one-half and three-quarters. ꠶ can follow these signs to make the grouping of a numerical entry clear when nearby figures could otherwise be read in different ways. The fraction sign supplies the value; the ring-shaped mark helps you read the entry correctly.

This use is documented in weight records and in measurements involving the kattha, a regional unit of land area. It belongs to practical record-keeping, not just abstract mathematics.

Where does this notation come from?

It belongs to a shared tradition of Indian numerical notation.

The wider system served money, weights, land measurements and time. It appears in documents using several scripts, including Kaithi, Gujarati, Mahajani, Maithili, Modi and Takri. These are writing systems, not names for different values of the mark. The fraction system is documented from at least the 16th century; this particular mark appears in George Grierson’s 1899 handbook of Kaithi.

Decimal currency and metric measurement reduced the system’s use after reforms in the late 1950s, though it continued into the 1970s. A Gujarati newspaper still used the system’s fraction signs to write times in 2004. That later example concerns the wider notation, not specifically ꠶.