SQUARE WITH BOTTOM HALF BLACK U+2B13

BlockMiscellaneous Symbols and Arrows
CategoryOther Symbol
UTF-80xE2 0xAC 0x93
UTF-160xFF 0xFE 0x13 0x2B
UTF-320xFF 0xFE 0x0 0x0 0x13 0x2B 0x0 0x0
HTML⬓
Pythonu"\u2B13"