This paper presents and discusses the analysis of the lithic assemblage from a newly discovered archaeological site, Cueva Alí Mustafá, located in the eastern sector of the Tandilia Range (Buenos Aires, Argentina). Lithic artifacts associated with several hearths and scattered fragments of charcoal were dated in 10,450 ± 38 and 9032 ± 30 radiocarbon years ago, respectively. The site is interpreted as an ephemerally occupied camp in which lithic knapping activities were carried out, related to the late and final stages of stone-tool manufacture. The use of a wide variety of lithic raw materials from different sources was identified, most frequently two sedimentary varieties, one of which is a fine-grained rock whose source is more than 100 km from the archaeological site, and another, a medium-grained rock that is locally available. Other rocks were identified in lower frequencies, including, remarkably, the presence of silicified limestone which can be traced to more than 500 km away.Fil: Bonnat, Gustavo Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Humanidades. Departamento de Historia. Laboratorio de Arqueología Regional Bonaerense; Argentina