STOCKTON — Cellist Amit Peled brings a very special musical instrument with him when he returns to perform with the Stockton Symphony on Saturday, April 12, at 6 p.m. in Delta College’s Atherton Auditorium. After playing for legendary Pablo Casal’s widow in the summer of 2012, she selected him to take the virtuoso’s prized cello on one last world tour. Peled was given the 1700s Goffriller cello on loan and he has been touring the country ever since, performing with Casals’ cello—which will eventually be put on permanent display in a Madrid museum, never to be played again.