Geochemistry, mineralogy and sulfide mineralization in quartz Veins in South of Mashhad

Shelgerd area is located south of Mashhad, N.E of Iran, within Binalud Structural Zone. This region is affected by regional metamorphism, slate and phylite are the main metamorphic rocks of the area. Teriassic slate, phyllite, sandstone and Jurassic conglomerates crop out parallel to Sang bast- Shandize fault. Mineralization occurred as vein type, with trend of N65E to N50W with 75 degrees to the south west. In superficial zones slags are common. primary ores are quartz, pyrrhotite, chalcopyrite, galen, orpiment, realgar and secondary minerals are malachite, azurite, covellite, goethite, hematite, limonite and covellite. Stream sediment geochemical sampling method shows anomalities of Ag, Cu, Pb, Zn, Fe elements. In The heavy mineral samples, some mineral such as orpiment, realgar, gold, pyrite and cassiterite are recognized. Also, geochemical analysis conducted on the small rock samples from surface of gold veins and old tunnel show the amount of gold is about 4.424 ppm, silver 8.42 ppm, copper %4.4964, iron %1.4349, laed %0.6939, and zinc %0.2825. Chemical analysis of galena shows high concentration of Ag, Sb, Bi. Depends on the ratio of Sb/Bi, mineralization temperature is low to medium and epigenetic type. According to mineral galena, crystals are the primary type.