[1] Mineral alteration is essentially governed by the laws of thermodynamics related to energy conservation, relevant to environmental conditions, often in presence of catalysts, the most common and influential being water (H2O).
Some minerals are members of a solid solution series and are samples of a range of compositional changes in a continuum, and thus are not 'mineral alteration' products.
Kaolinization refers to the alteration of alkali feldspar into the clay mineral kaolinite in the presence of slightly acidic solutions.
Rain readily dissolves carbon dioxide (CO2) from the atmosphere, promoting weathering of granitic rocks.
Diagenesis is a likely culprit that involves volumes of water and fairly low heat, as an ionic exchange catalyst.
Uralitization is the process of deuteric alteration of pyroxene (most commonly augite) to form amphibole (actinolite-tremolite).