ErAu4

ErAu4 is an intermetallic compound combining erbium (a rare earth element) with gold in a 1:4 atomic ratio. This material belongs to the rare earth–precious metal intermetallic family, which exhibits high density and distinctive mechanical properties arising from strong metallic bonding between the two dissimilar elements. ErAu4 is primarily of research and specialized industrial interest rather than a commodity material; it is investigated for applications requiring the combined benefits of rare earth elements (such as electronic or magnetic properties) with gold's chemical stability and nobility.