The Salt Lake (Tuz Golu) is the second largest lake in Turkey and also is one of the greatest salty lakes in the world. Salt Lake has a great salt potential. The salt was produced in large quantities on saltpans in the Salt Lake. In this study, a detailed mineralogical investigation was carried out with salt crust samples and unconsolidated muddy sediments, below the salt crust collected from the Kaldirim Saltpan in the Salt Lake. The salt crust and below the salt crust (1 - 20 cm) evaporate mineralogy were determined by X-ray diffraction method. The analysis results show that the salt crust was in composition of halite, gypsum and kieserite; muddy sediments and below the salt crust which was in the composition of gypsum, magnesite, thenardite, polyhalite, aragonite and montmorillonite. The mineralogical variations of the participated salts indicated that, the chemical compositions of brines vary significantly between the Na-K-Mg-Ca-Cl type and the Na-K-Mg-Cl-SO4 type.