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This study investigates environmental signals of early mining activities in Garpenberg by analysing sediment core samples from three lakes: Gruvsjön, Stora Jälken, and Trehörningen. In addition, a comparison between two methods for analysing the geochemical composition of lake sediment, energy dispersive X-ray fluorescence (ED-XRF) and wavelength dispersive X-ray fluorescence (WD-XRF) was conducted for Gruvsjön. Age-depth models for the sediment profiles was conducted by matching known peaks in historical atmospheric Pb-pollution as points of reference together with the introduction of Norway spruce (Picea abies) pollen in Gruvsjön, and lake formation in Stora Jälken and Trehörningen. The earliest signs of mining activity in Gruvsjön date back to approximately 300-500 CE, as evidenced by the gradual increase in Zn levels. Similarly, the earliest signs of anthropogenic influence in Stora Jälken are around 500 CE, likely related to Zn extraction. However, the absence of changes in other mining-related elements suggests that the observed geochemical shifts in Pb, Cu, Fe, Br and Ti must be explained by other factors. Furthermore, no clear evidence of local mining was identified around Trehörningen. Hence, the observed geochemical changes in this lakes sediment record were attributed to other anthropogenic influences such as damming and agriculture. Lastly, the method comparison between ED-XRF and WD-XRF demonstrates a high degree of coherence for most of the tested elements from the sedimentprofile from Gruvsjön.