DETROIT — Maxine Powell, who was responsible for developing the charm, grace and style of Motown Records’ artists during the Detroit label’s 1960s heyday, died Monday at age 98.

Motown Historical Museum CEO Allen Rawls said Powell died of natural causes at a hospital in Southfield, Mich.

She didn’t sing or write songs, but those associated with Motown say Powell was as essential to the label’s operations as any performer or producer.

She directed the label’s Artists Development Department, also known as “Motown’s Finishing School.” Through it, she emphasized to many artists — including Smokey Robinson and the Miracles, the Jackson Five and the Supremes – how they should carry themselves, treat people and dress.

Motown founder Berry Gordy said the training school was the only one of its kind offered at any record label.

“She brought something to Motown that no other record company had,” Gordy said in a statement Monday. “She was a star in her own right – an original. She will always be remembered for her style and class, and she instilled that into the Motown artists by teaching them how to walk, talk and even think with class.”

Powell’s passing comes less than two months after she was honored at the museum by Robinson and others.

“She was such an important, integral part of what we were doing here at Motown,” Robinson said at the Aug. 26 event held at the famed Hitsville, U.S.A, building.

“It didn’t matter who you became during the course of your career – how many hits you had, how well your name was known around the world,” he said. “Two days a week when you were back in Detroit you had to go to artists’ development. It was mandatory.”

Born in Texarkana, Texas, Powell was raised in Chicago, where she began her career as an actress.