Evidences of epithermal mineralization at Bidook gold vein deposit (east of Iran), based on geology, alteration, mineralization, geochemistry and thermometery data.

Bidook deposit is located about 10 km southeast of Bajistan, Khorasan Razavi Province, in the northern part of Lut Block. Geology of the area includes andesite and pyroclastic units. Alterations in these rock units include propylitic, silicic and argillic. Mineralizations were formed as veins of quartz sulfide  that are cut through andesitic and pyroclastic rocks. These veins have massive texture and pyrite is the primary sulfide mineral that is often weathered to iron oxides, so veins have orange to yellow appearance. Litho-geochemical studies of alteration and mineralization veins revealed anomalies of gold element (between 3 to 201 mg/t and even in one of samples it is up to 1173 mg/t).  One type of fluid inclusion as liquied rich, on the basis of fluid inclusion assemblage in quartz at quartz- fe oxide veins, has been identified. Thermometric analysis on two-phase primary (L+V) fluid inclusions shows that temperature of mineralization ranges between 202 ͦ C to 273 ͦ C and salinity in the range 15.76 to 19.99 wt% of NaCl equivalent. Host rock composition, mineralogy, formation temperature, alterations and geochemistry data of the Bidook area make it similar to epithermal deposits.