Dear Mr. Valentini,

please scout the papers of Cahit Helvaci and co-authors. It is the best source area for your question.

H.G.Dill

Dear prof. Hill, thanks for your suggestion. I browsed the works of Helvaci and co-workers, but they seem to be mostly focussed on the geology of borate deposits and I had no luck so far to find any thermodynamic data of the single phases.

I wonder if there is a very good source of this data around for such specific minerals. Check this out: Robie and Hemingway Thermodynamic properties of minerals and related substances (1995) - USGS publication. Make sure you have the right values specifically for the temperature you need.

Dear Ilya, it is a very interesting reference, thanks for that. Unfortunately no data about colemanite. I found data for the standard enthalpy and entropy of formation on a special thematic publication of the Mineralogical Society of America, but unfortunately it does not report heat capacity data.

Dear Mr. Valentini

I am looking for standard heat capacity Cp of colemanite. If you found it, would you share it with me.