FLORENCE, Italy (AP) — An ongoing restoration of one of Leonardo da Vinci’s most famous works, “Adoration of the Magi,” has revealed new details and colors in the painting and in Leonardo’s techniques — and confirmed that others helped paint it.

Leonardo began the large-scale work in 1481 but left it unfinished after he was transferred from Florence to Milan.

Florence’s Uffizi Gallery shelved plans in 2002 to restore it after tests showed it was in good health. But by 2011 restoration became necessary.

Officials on Tuesday released findings of the first phase of the restoration, which is scheduled to be completed in 2015. They said the initial removal of grime showed new details and color in the work and gave insight into Leonardo’s techniques, but also made clear that other artists were involved.

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