This study aims at analyzing the mineralogical, chemical, and structural characteristics of flint raw material used for the production of prehistoric stone tools in NW Belgium. Understanding these characteristics is important to recognize their value for tool making and even tool use during prehistory. Due to its formation process, flint is defined by a wide variety of internal structures, chemical variations, and impurities. Moreover, alteration processes cause additional chemical and structural changes complicating the study of this material. Archaeological artifacts often display alteration features, mostly expressed as patination or burning, leading them to be regularly discarded from the functional analysis of lithic tools. By not incorporating these artifacts, our understanding of the investigated assemblage is biased. It is therefore important to investigate the influence of flint characteristics on its weathering behavior, and the impact of preservation of prehistoric use‐wear traces on flint artifacts. The characteristics of flint raw material and natural patination were studied using a combination of different techniques, such as macroscopic analysis, optical microscopy, X‐ray fluorescence, and high‐resolution X‐ray computed tomography. This resulted in a detailed description and distinction of the different flint variants used on prehistoric sites in NW Belgium and a good understanding of patination.