Zanabazar Square Initial Double-Lined Head Mark

It marks the beginning of a Zanabazar Square text. It is structural punctuation, not a spoken word; the wider Tibetan head-mark tradition called yig mgo also marks a text or section opening.

Zanabazar devised the script for writing Mongolian, Sanskrit and Tibetan. A proposal dated 2015-12-03 says it likely predates Soyombo, a separate script, but leaves its exact creation date open.

A manuscript folio cited in a proposal dated 2015-12-30 shows the paired double-lined opener and closer 𑩅𑩆, corresponding to the Tibetan pair ༄༅. That proposal does not establish when this exact Zanabazar Square mark first appeared.

Why does 𑩅 render differently?

Font coverage and shaping software affect its appearance. It can carry candrabindu, a nasalization sign, or anusvara, a nasal sound marker; 𑩆 closes its double-lined sequence.

BabelStone reported in February 2018 that Microsoft applications on Windows 10 lacked complex script shaping and Firefox rendered the script incorrectly, while Chrome with the HarfBuzz text-shaping engine handled it. Those are historical results, not a current guarantee.

If the mark appears as a box or its attached signs shift, the font or text renderer is usually the cause.