Silicate glasses heat capacity

Stebbins I F, Carmichael I. S. E. and Moret L. K. (1984). Heat capacities and entropies of silicate liquids and glasses. Contrib. Mineral Petrol, 86 132-148. 

Owing to their polymeric nature, many silicate compounds and systems tend to form glasses. When cooling rapidly from the molten state, a part of the sample crystallizes, while the other part remains glassy. This is the main disadvantage while measuring their heat capacity, heat content, enthalpy of fusion, and mixing. 

The mean isobaric specific heat capacities Cp (2Q°C 100 °C) listed in Table 3.4-16c were measured from the heat transfer from a hot glass sample at 100 °C into a liquid calorimeter at 20°C. The values of Cp 20°C 100 °C) and also of the true thermal capacity Cp 20 °C) for silicate glasses range from 0.42 to 0.84 J/gK. 

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