<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>EuPt<sub>4</sub>B (I), Eu<sub>3</sub>Pt<sub>7</sub>B<sub>2</sub> (II), and Eu<sub>5</sub>Pt<sub>18</sub>B<sub>6‐</sub><sub>x</sub> (III) are synthesized by arc melting of the constituent elements using excess Eu due to its high volatility.</p> </abstract>