of the measurements in this direction have utilized superconducting aluminum cavities, other recent work has involved qubits coupled to copper cavities with coherence times approaching 0.1 ms. The copper provides a good path for thermalizing the cavity walls and qubit chip, although the substantial cavity loss makes conventional dispersive qubit measurements challenging. We are exploring various approaches for improving the quality factor of three-dimensional copper cavities, including electropolishing and coating with superconducting layers of tin. We have characterized these cavities on multiple cooldowns and found the tin-plating to be robust. In addition, we have performed coherence measurements on transmon qubits in these cavities and observed promising performance.