Thermal conductivity and mineral composition of some Transvaal rocks

"The thermal conductivity and mineral composition of 42 samples of various rocks from the Transvaal are given. An attempt to correlate conductivity and composition shows qualitative rather than quantitative agreement for most samples. This is attributed to the complexity and degree of alteration of the rocks and in some cases to lack of data on the conductivity of monomineralic aggregates. Porosity is shown to be a dominating factor influencing the conductivity of some of the igneous rocks."