Abstract: Mineral resources appraisal has been an important research subject for geoscientists around the world in the past three decades. Significant progress has been made in development of statistical techniques and estimation methodologies for mineral resources. Integration of multiple data sets, either by experts or statistical methods, has become a common practice in estimation of mineral potentials. However, real effect of these methodologies is at best very limited in term of uses for government macro policy making, resource management, and mineral exploration in commercial sectors. Several major problems in data integration remain to be solved in order to achieve significant improvement in the effect of resource estimation. Some critical issues, considered being critical and fundamental in mineral resources appraisal, are addressed in this paper. Issues related to randomness of mineral endowment, intrinsic statistical relations, exceptionalness of ore, intrinsic geological units, and economic translation and truncation, are discussed in this paper. Moreover, a number of specific important technical issues in information synthesis are also identified as well, including information enhancement, spatial continuity, data integration and target delineation. Finally, a new concept of dynamic control areas is proposed for future development of quantification of mineral resources.