U+25C8 White Diamond Containing Black Small Diamond

U+25C8 was added in Unicode version 1.1 in 1993. It belongs to the block U+25A0 para U+25FF Geometric Shapes in the U+0000 para U+FFFF Basic Multilingual Plane.

This character is a Otro símbolo and is commonly used, that is, in no specific script.

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 Other Neutral. When changing direction it is not mirrored. If its East Asian Width is “narrow”, U+25C8 forms a word with similar characters, which prevents a line break inside it. Otherwise it allows line breaks around it, except in some numeric contexts.

The CLDR project calls this character “rombo hueco con rombo relleno dentro” for use in screen reading software. It assigns these additional labels, e.g. for search in emoji pickers: dentro, hueco, relleno, rombo.