A natron source at Pikrolimni Lake in Greece? Geochemical evidence

The geochemical conditions that are responsible for the formation of “Chalastraion nitron” in the basin of Lake Pikrolimni (Northern Greece) were investigated in this study. The goal of the study is to confirm Pliny's description: “at Clitae in Macedonia it is found in abundance the best, called soda of Chalestra…” The ion-specific interaction model based on Pitzer's equations showed that the lake brine samples are saturated versus carbonate–bicarbonate sodium and sodium–chloride–sulfate minerals. The results of individual X-Ray Diffraction (XRD) analyses on the evaporative deposits showed that the salts consist mostly of trona, burkeite, thenardite and halite confirming Pliny's description.