Situated between the Altai Mountains and the Chinese Loess Plateau, the current territory of Mongolia played a pivotal role in Pleistocene human population dynamics in Northeast Asia with archaeological evidence suggesting the existence of cultural links with southern Siberia beginning in the Late Pleistocene. Here, we present preliminary results from the newly discovered site of Kharganyn Gol 5 in northern Mongolia. The results obtained from the Kharganyn Gol 5 site allow new reconstructions of chrono-cultural sequences and human behavior in eastern Central Asia. The site has yielded evidence of human occupation corresponding to several phases of the regional Upper Paleolithic. In addition, we present the first evidence of human occupation of the region prior to Greenland Interstadial 12 (GI12; 40,000–43,000 BP) and discuss the implications of such data. The Kharganyn Gol River basin contains sedimentary rock formations including numerous raw material outcrops, containing various types of chert. Prehistoric people used all these chert varieties for tool production, but the modes of raw material exploitation changed through time. This paper reports the presence, unique in Central and North Asia, of a non-utilitarian object made of muscovite mica in an Initial Upper Paleolithic assemblage in Archaeological Horizon 5 of the Kharganyn Gol 5 site.