During the last thirty years profound developments in expe-
rimental techniques to measure high temperature and pressu-
res and thermodynamic properties of minerals have occurred.
This technical development has been matched by an increased
sophistication in applying theoretical methods to obtain new
data or improve the quality of existing data. Using these
newtechniques, Assessed Thermodynamic Data on Oxides and
Silicates represents the successful attempt of the authors
to develop an internally systematized data base which satis-
fies the constraints of calorimetric measurements, phase
equilibrium data, measured thermophysical properties of a
phase, and heat capacities and entropies estimated from lat-
tice vibrational models.