Measured values of thermal conductivity from crystalline rocks are compared with values calculated from the mineral content using the layered model. First, thermal conductivity is estimated using data based on quasi-isotropic mixtures of fragments or powder. Second, the approach is applied on core data considering the anisotropy of some rock forming minerals. The numerical value of estimated thermal conductivity is controlled by the quartz content. Sheet-silicates control anisotropy and fabric in gneisses and their thermal consequences. If information about the fabric of the rock is available, the anisotropy of minerals can be considered in a layered model and this improves the estimation of thermal conductivity from mineral contents. ¿ American Geophysical Union 1993