The sp. heat of kurnakovite (2MgO.3B2O3.15H2O) was measured at 65-310 K by using the adiabatic calorimeter. The math. relation between the sp. heats and temps. is given. The sp. heat of kurnakovite at 0-65 K was calculated by Debye-Einstein function. The entropy (S), enthalpy (H), and Gibb's free energy (G) were calculated and are tabulated for intervals of 5 K at 65-310 K. At 299.15 K, S = 723.4 ?4.8 J/K.mol, H = 118.8 ?0.2 kJ/K.mol, G = 327 ?5.4 J/K.mol.

Key words: THERMODYNAMIC PROPERTIES, CAMSELLITE, MAGNESIUM OXIDE, HYDRATE, ENTROPY, ENTHALPY, SPECIFIC HEAT, BORON OXIDE