The US Department of Energy (DOE) has sponsored an initiative to improve the thermal efficiency of Concentrating Solar Power (CSP) systems. To approach parity with conventional fossil fuel-based electricity generation, the operating temperature of the CSP power cycle must exceed 700°C with integrated thermal energy storage. The materials used to house this high-temperature heat transfer media must be thermally stable and corrosion resistant. However, the temperature-dependent thermophysical properties of commonly used containment materials (nickel alloys and alumina-based firebricks) are either not well known or poorly understood. In this report, the high-temperature thermal properties of thirteen (13) candidate containment materials proposed by the CSP community are tested using laser flash analysis and differential scanning calorimetry.