Heusler intermetallics are a class of compounds that share the same crystal structure and chemical formula XY₂Z, where X and Y are transition metals, and Z is a main group element. These intermetallics exhibit many unique and desirable properties such as thermoelectricity, magnetic shape memory, and even superconductivity. Previous neutron diffraction studies have shown that the Heusler MnAu₂Al exhibits a coexistence of ferromagnetism and spiral magnetism at low temperature, while isoelectronic MnCu₂Al is only ferromagnetic. We propose the spiral magnetic structure of MnAu₂Al is due to spin-orbit coupling resulting from the gold atoms. Spin-orbit coupling, or the interaction between an electron’s spin and orbital motion, scales with Z⁴, where Z is atomic number, making the effect much stronger for heavy elements such as gold. Samples of each MnAu₂Al and MnCu₂Al were made through rapid assisted microwave heating and arc melting. Samples were first characterized using a combination of X-ray diffraction and scanning electron microscopy, which elucidated the phases present and their compositions in each sample. This allowed us to tune the starting composition until we obtained a phase pure sample. Magnetic measurements of MnAu₂Al indicate an antiferromagnetic (spiral) phase below 110K, with a metamagnetic transition to ferromagnetic at an applied field of 2 T. Future work will use computational tools to determine if the energy needed to induce spiral magnetism corresponds to the energy attributed to spin-orbit coupling. This understanding of the effects of spin-orbit coupling will be useful in tuning magnetic properties of other materials by simply changing their chemistry.