They used paraffin wax as the phase-change material (PCM ... “The hybrid-nano/PCM samples are prepared, and their morphology, structure, thermal stability, thermal conductivity, and phase ...

But he did reveal some key ingredients. Katzel: Inside of a lava lamp, you've got wax, which is mostly paraffin wax. That's your lava. Jones: Paraffin wax is a common wax made from petroleum.