U+2B1B, ⬛
BLACK LARGE SQUARE

[U+2B1A]
Miscellaneous Symbols and Arrows
[U+2B1C]
Presentations of ⬛︎
Text
style
Emoji
style
⬛︎ ⬛️
Note: Character's appearance
may be different on each system.
Text style is forced with ︎
and emoji style with ️

Emoji