The design and experiment of a phase reconfigurable RA unit cell enabled by a COSMIX was proposed. A phase shift of 200° was demonstrated at 3 GHz with only 1.2 dB of loss. Deviations were observed between the measured and simulated results but the trends are in agreement. The 0.4 dB baseline loss shown in Fig. 4 is a measurement of the waveguide with no patch or other materials present. Additional losses may be due to the actual dielectric properties of the oil and colloidal material. Discrepancies in the phase behavior are attributed to fabrication challenges as well as the more dominant and observed effect of particle settling within capacitive gap of the COSMIX. Ongoing work includes the automation of a fluid delivery system, mixing mechanisms for control of colloidal material in the dispersion, and further stabilization of the dispersion to prevent aggregation within the gap.