Catalyst for the metathesis of olefin(s)

A metathesis catalyst consisting essentially of a transition metal or oxide thereof supported on a high purity silica support, said high purity silica support possessing low amounts of acidic or basic sites such that in a reaction of pure 1-butene over said catalyst under metathesis reaction conditions the reaction possesses a weight selectivity to hexene-3 of at least 55 weight percent, wherein the high purity silica support possesses less than about 150 ppm magnesium, less than about 900 ppm calcium, less than about 900 ppm sodium, less than about 200 ppm aluminum and less than about 40 ppm iron.