The carbonate clumped isotope paleothermometer has shown its promises for many implications, including paleo-climate, paleo-latimetry, paleo-biology, thermal history of basins and diagenesis.
However, empirical calibrations of clumped isotopes do not extend beyond 80˚C. All applications for carbonates precipitated at tempertures in excess of 80˚C consequently rely on the assumption that the curve derived from low-tempertature calibrations can be extrapolated to higher temperatures. Although this may be a correct assumption, rigorous testing is required to establish it.
Performing precipitations at a controlled temperature in excess of 90˚C is more challenging as water evaporates under ambient pressure, and so a well-designed pressurized vessel is needed. However, calibrations at reservoir conditions (ambient temperatures of 100-200˚C) is crucial to increase confidence in clumped isotope applications to these systems.