Mineral deposit evaluations require the expertise of geologists, mining engineers, process engineers, and metallurgists to collaborate for a reasonable assessment of risks and opportunities. The deposit evaluation process follows international guidelines and codes such as NI 43 101 in Canada and SK 1300 in the USA. These guidelines provide guidelines for minimum scientific studies required for a reliable outcome. GeometallurgyGeometallurgy is an integral part of the deposit evaluation process. This paper uses various examples to demonstrate how geometallurgical issues are unique for each deposit and require collaboration between geologists and process engineers for a reliable evaluation.