Code point
U+25FC
Glyph appearance depends on your fonts.
U+25FC
SmU+25FC BLACK MEDIUM SQUARE is a Unicode 16.0.0 character in the Math Symbol category. It belongs to the Geometric Shapes block.
Choose the representation you need, then copy its value.
U+25FC
9724
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E2 97 BC
25FC
000025FC
%E2%97%BC
\u25FC
\u25FC
\u25FC
\25FC