A 12-year-old visitor to the Detroit Institute of Arts stuck a wad of gum to a $1.5 million painting, leaving a stain the size of a quarter, officials say.

The boy was part of a school group from Holly, Mich. that visited the museum on Feb. 24, officials say. They say he took a piece of Wrigley's Extra Polar Ice gum out of his mouth and stuck it on Helen Frankenthaler's The Bay, an abstract painting from 1963.

The museum acquired the work in 1965 and says it is worth about $1.5 million.

The gum stuck to the painting's lower left corner and did not adhere to the fiber of the canvas, officials told the Detroit Free Press. But it did leave a quarter-sized chemical residue, said Becky Hart, assistant curator of contemporary art.

The museum's conservation department is researching the chemicals in the gum to decide which solvent to use to clean it. The museum hopes to make the repair in two weeks and will keep The Bay on display in the meantime, she said.

"Our expectation is that the painting is going to be fine," Hart said.

Holly Academy director Julie Kildee said the boy had been suspended from the charter school and says his parents also have disciplined him.

"Even though we give very strict guidelines on proper behavior and we hold students to high standards, he is only 12 and I don't think he understood the ramifications of what he did before it happened, but he certainly understands the severity of it now," said Kildee.

Copyright 2006 Associated Press