Abstract
It was found that the transformation of siliceous stone, from quartz to cristobalite, was the primary reaction. The rate constants of the conversion of several siliceous stones (contrasted origin) were calculated. Influence of grain sizes on the velocity of the conversion was investigated. The effect of irreversible thermal expansion of the unisotropic polycrystal aggregate to its apparent density is calculated theoretically, and experimentally measured. Accurate determination of the transformation verocity, and experimentally measured. Accurate determination of siliceous stone has became possible by taking the effect into consideration.
