Does anyone know the name of this symbol? [duplicate]

This question already has an answer here:

Does anyone know the name of this rotated, filled in, black square symbol?

marked as duplicate by siracusa, marmot, Kurt, JouleV, RaajaMar 24 at 6:23

• \blackdiamond (mathabx), \filleddiamond (MnSymbol), \Diamondblack (txfonts), \FilledDiamondshape (ifsym), \FilledBigDiamondshape (ifsym), \DiamondSolid (bbding) – Steven B. Segletes Mar 23 at 23:09
• See e.g. here: tex.stackexchange.com/a/196792/117050 – Skillmon Mar 23 at 23:11
• – Steven B. Segletes Mar 23 at 23:15
• Another option using amssymb and graphicx: \rotatebox[origin=c]{45}{$\blacksquare$} – Sandy G Mar 23 at 23:20
• The stix fonts have this in several sizes: \mdlgbkldiamond, \mdblkdiamond, \smblkdiamond. All are "ordinary" characters, but can be assigned another class. – barbara beeton Mar 24 at 2:40

Some packages (e.g., txfonts) change many symbols. One possibility is to use amssymb and rotate the \blacksquare symbol using \rotatebox from the graphicx package.

Depending on whether you're using the symbol as a relation, operation or ordinary symbol, you can use the following:

\documentclass{article}

\usepackage{amssymb,graphicx}

\newcommand{\blackdiam}{\rotatebox[origin=c]{45}{$\blacksquare$}}

\begin{document}

$a\blackdiam b$

$a\mathbin{\blackdiam}b$

$a\mathrel{\blackdiam}b$

\end{document}


Of course you can include the \mathbin or \mathrel in the macro. You can also use \mathchoice or \mathpalette so your symbol can be used in \scriptstyle or \scriptscriptstyle.