CHICAGO (AP) — Once the lid was off the wood coffin holding the 2,500-year-old mummified remains of a 14-year-old Egyptian boy, scientist J.P. Brown could relax.

The conservator at Chicago’s Field Museum and three other scientists had just used clamps and pieces of metal to create a cradle to lift the fragile lid. Wearing blue surgical gloves, they slowly lifted the contraption containing the coffin lid and carefully walked it to a table in a humidity-controlled lab at the museum.

“Sweet!” Brown said, after helping set the lid down. He later added: “Oh yeah, god, I was nervous.”

The well-planned routine came Friday as scientists started conservation work on the mummy of Minirdis, the son of a stolist priest. The mummy needs to be stabilized so it can travel in the upcoming exhibit, “Mummies: Images of the Afterlife,” which is expected to premier next September at the Natural History Museum of Los Angeles County. It is expected to travel to the Denver Museum of Nature and Science in fall 2016.

The Field Museum has had the mummy since the 1920s, when the institution received it from the Chicago Historical Society. It’s part of the museum’s collection of 30 complete human mummies from Egypt.

“There’s always a risk of damage,” said Brown, who did the work in a lab filled with plastic-covered examination tables set behind a large window to let schoolchildren watch his daily work. “So we like to handle these things as little as possible.”