Barite occurrences east of Istanbul (NW Turkey) are compared major mineralogical and geochemical properties, and identified depositional origins. Sile barite occurrence, which is near Blacksea, north east of Istanbul, is alternated with Triassic sandstone. Petrographic observations reveal that barite grains are found out in the sand stones. Chemical analyses are conducted on eighteen samples via AAS (Atomic Absorption Spectroscopy) equipment for detection of Cu, Zn, Pb, Sr, Cd and Ni concentrations. Because of a vein shape, the occurrence is evaluated as a hydrothermal origin. However, microscopic studies, low Pb, Zn and Sr concentration and the presence of arkose show that the barite is formed by sedimentary.