The tetragonal chemically-ordered L10 FeNi phase has recently attracted significant attention for advanced permanent magnet applications due to its compelling magnetic properties, low cost and good availability of its constituent elements. While L10 FeNi has been found in meteorites, bulk synthesis has not yet been achieved due to its low order-disorder temperature of 320°C, below which phase formation is kinetically limited. The key objective of this proposed research is to explore pathways to synthesize L10 FeNi in earthly timeframes. Preliminary synchrotron XRD testing of our samples has provided initial evidence of successful formation of L10 FeNi. The higher resolution and flux available at HRPD provide a unique opportunity for L10-FeNi phase identification and characterization, to unambiguously prove the achievement of this phase in a laboratory setting.