The mountainous areas of the Carpathian basin have provided a wide spectrum of siliceous rocks for prehistoric people. Although the presence of outcrops of a kind of chert, named Buda hornstone was already known by geological and petrographic investigations, the developing Hungarian petroarchaeological research did not pay much attention to this raw material. Its archaeological perspectives have been opened by a discovery made at the Denevér street in western part of Budapest in the 1980s. During the excavations of the flint mine, not much was known about the distribution of this raw material in the archaeological record. Since then the growing amount of archaeological evidences showed that its first significant occurrence in assemblages can be dated to the Late Copper Age Baden culture, and it became more abundant through the Early Bronze age Bell-Beaker culture until the Middle Bronze Age tell cultures. Until now, 15 outcrops of the Buda hornstone have been localised on the surface. Based on thin section examinations taken from two different outcrops, we have made a clear distinction between three variants. In the last few years, archaeological supervision has been conducted during house constructions, suggesting the Buda hornstone occurrence takes the form of a secondary autochthonous type of source. In the framework of our research program, a systematic check of the raw materials is planned in the lithic assemblages of the nearby prehistoric sites, as well as to look for extraction pits or other mining features with the application of geophysical methods and a thorough analysis of the surface morphology