Caesium auride is the inorganic compound with the formula CsAu.

[2] CsAu is obtained by heating a stoichiometric mixture of caesium and gold.

The two metallic-yellow liquids react to give a transparent yellow product.

[3] Despite being a compound of two metals, CsAu lacks metallic properties since it is a salt with localized charges; it instead behaves as a semiconductor with band gap 2.6 eV.

[4] The compound hydrolyzes readily, yielding caesium hydroxide, metallic gold, and hydrogen.