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This run features an aqueous solution that is approximately 15.5 wt.% Na2SO4. Initially, the pressure was about 154 MPa. 08/08/20 23:45:43: The run starts at 285 K; there were likely a very few seed crystals present in the system -- as the system is cooled, the volume does not decrease. Instead, it increases slightly due to the growth of mirabilite crystals, which are visible coming in from the right hand side of the screen. 08/08/21 15:56:03: After supercooling to 252.57 K, the remaining liquid in the system freezes. Since this is in the Ice Ih regime, the volume and pressure increase. The solution is frozen in the connecting tubing so that the pressure and volume transducers do not fully reflect the conditions inside the pressure cell. 08/08/22 11:53:03: The solution in the connecting tubing finally melts enough that the volume can change, but condensation has covered the lenses, so it is not possible to be sure the volume changes correspond to eutectic melting in the sample. Cooling slightly to reverse the transition is initially successful, but then the system locks up again. 08/08/22 17:52:03: A second slow warming pass produces a reversible transition consisten with eutectic melting. 08/08/23 04:13:03: The image brightens as condensation is cleared off the lenses as the remaining mirabilite crystals come into view.
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