As the title of the book suggests, the two key areas in focus here are crustal evolution and metallogeny. Crustal evolution refers to the changes that the Earth's crust has gone through the geological past. These are due to the effects of the interaction of and changes in the mantle-crust system, the atmosphere, the hydrosphere and the biosphere, or even otherwise. The changes may be chemical or physical, or both. Metallogeny is the genesis of metallic mineral deposits. This term has been used in the book in its conventional sense, although the phosphatic, sulphatic (anhydrite/gypsum, barite), carbonate (magnesite) deposits and even precious stones like diamond are included for the sake of relevance.

Indian geology is now over 150 years old. During the first 100 years or so, the colonial government took interest in exploring mineral resources in India. During the post-independence time, substantial attention was paid to increase the resource (material) base of the country that would ultimately improve the quality of life of the newly liberated people. Interestingly, Pandit Jawaharlal Nehru, the first Prime Minister of India, was a student of Geology at Cambridge. By now a lot of information, but by no means adequate in all respects, on Indian geology has been accumulated. These need to be analysed and synthesised from time to time for whatever they are worth, besides being augmented.

Quite a few texts on modern ore geology are in circulation now.