This character is a Nonspacing Mark and inherits its script property from the preceding character. It is also used in the scripts Duployan shorthand, Latin, Syriac.
The glyph is not a composition. Its width in East Asian texts is determined by its context. It can be displayed wide or narrow. In bidirectional text it acts as Nonspacing Mark. When changing direction it is not mirrored. U+030A prohibits a line break before it. The glyph can be confused with 19 other glyphs.
El Wikipedia tiene la siguiente información acerca de este punto de código:
A ring diacritic may appear above or below letters. It may be combined with some letters of the extended Latin alphabets in various contexts.