Abstract: Geochemical distribution data (several tens of millions) of 39 elements were obtained in China's national geochemical mapping program carried out for 24 years over more than 6 million km2 of China's territory. By examining the flood of data, the authors have found much broader geochemical patterns other than dispersion halos and dispersion trains which have been the main subjects of study during the 60 years' development of exploration geochemistry. Such broader geochemical patterns are geochemical anomalies, geochemical provinces, geochemical megaprovinces and geochemical domains. They are surface expressions of the internal structural features of large blocks of rock with higher metal contents. Those large "geochemical blocks" are the net results of the Earth's original heterogeneity and the distribution and redistribution of metals from the initiation and evolution of the Earth up to the present days. The authors got a new idea that the large can provide large metal endowments necessary for the formation of large to superlarge geochemical blocks ore deposits. To explore the internal structure of the geochemical block of a certain element may reveal the trajectory of gradual concentration and formation of ore deposits of that element in the geochemical block. The new geochemical block concept is changing the mineral exploration strategy and methodology in China, providing a powerful tool for global mineral potential assessment and inspiring new ideas for exploration geochemistry, ore-genesis and metallogeny.