A lock of hair belonging to Rolling Stones star Mick Jagger will be auctioned for charity on July 3, for an estimated $2,300 (€1, 723) and $3,100 (€2,322), according to British auction house Bonhams.

The piece of hair belonging to the 69-year-old rocker is believed to date back to the early-to-mid 1960s.

According to the auctioneer, Chrissie Shrimpton, who Jagger dated just after his time as a London School of Economics student, the clump of hair was collected and freshly washed by Shrimpton's grandmother.

A statement on the Bonhams website reads: "The statement, from Chrissie Shrimpton, confirms that, unbeknown to her at the time, this lock was saved by her grandmother when Mick and Chrissie were staying at her parents' farm. Apparently, on her grandmother's death, the hair passed to Chrissie's aunt and when she died, the hair was returned to Chrissie by a cousin taking care of personal effects."

All proceeds from the sale will go to the charity Changing Faces.