An electric guitar autographed by the surviving members of the Grateful Dead has sold at auction for $526,000 (£328,750). Bidding on the six-string instrument opened at just $5,000 (£3,125) during the band's first night of its 50th anniversary Fare Thee Well gigs last month (Jun15), before rocker Bob Weir played it onstage on 28 June (15) in Santa Clara, California. It was also signed by guest performers Trey Anastasio, Bruce Hornsby and Further's Jeff Chimenti and was snapped up by a devotee from Dallas, Texas on Sunday (05Jul15), as the cult jam band concluded its three-night run of farewell concerts at Soldier Field in Chicago, Illinois over the weekend (03-05Jul15). Other memorabilia raised a total of $250,000 (£156,250). All proceeds will be split evenly between 17 charities connected to the Grateful Dead.