Over the past four decades, Giles helped move the boundaries of basket weaving and earned international recognition for her art, which is characterized by coiled waxed-linen bases adorned with hammered metal or fine wire that brings to mind tree bark, fish scales, feathers or fur.

"You might look at her work and say 'Why is anyone calling this a basket?' It's not something you would put your apples in," said Lois Russell, a Boston-based artist, collector and former president of the National Basketry Organization. "She's one of the people who took the concepts of basketry technique and pioneered using them to make sculptural work."

Giles died April 11 of ovarian cancer. She was 73. She lived in a home along the river between Stillwater and Marine on St. Croix.

Born Mary Jo Mortenson in St. Paul to a father who made cabinets and a mother who quilted and did Norwegian rosemaling, she graduated from Mankato State University with a degree in arts education. She and her first husband, Doug Giles, moved to St. Louis, where he worked for the May Co. and she was a teacher in the upscale Ladue school district. After she and Giles divorced, she stayed in St. Louis.

She took a basketry workshop from Jane Sauer and John McQueen and started making art for sale. Her art dealer introduced her to Jim Harris, an architect and part-time art critic for the St. Louis Post-Dispatch, and the two started dating and eventually married.

Giles' career as an artist took off after she retired as a schoolteacher in the late 1990s, and she and Harris moved to Minnesota in 2006.

Her art required meticulous attention to detail. She created all the metal pieces she used in a workshop above her garage, using hammers and drills to flatten or coil the material. A typical day started at 8:30 a.m. in her studio, either weaving or adorning a woven base. She would work until lunch, and then spend the afternoon in the garden or in her metal workshop. After dinner, she would often go back to the studio. Harris always drove, because Giles' art could usually fit on her lap and she worked on it in the car.

"If we would go on a vacation, when we came back I would have to avoid her for a while because she was trying to make up for lost time," Harris said. "She always worked, and even after she had cancer, whenever she was well enough, she was in the studio."

There is no easy way to categorize Giles' art. At first what she made in some ways resembled a basket, but over the years the forms became more abstract. One piece looks like a boulder broken in two, another like a jellyfish, another like a series of stick figures standing atop each other.

"I admire the directness and honesty I see in tribal art and I try to incorporate those qualities in my own art," Giles said in her artists' statement for her retrospective exhibit at the Textile Center in Minneapolis in 2015.

Her work is in the collections of more than 15 museums throughout the United States, including the Minneapolis Institute of Art. She was recognized as Master of the Medium for fiber art and baskets in 2013 by the James Renwick Alliance, which supports the Renwick Gallery at the Smithsonian American Art Museum.

"She called herself a fiberist. She wouldn't say, 'I'm a basket weaver,' " said Karl Reichert, executive director of the Textile Center. "She encouraged all of us to think very broadly about the impacts of fiber art."

Giles is survived by Harris, her sister Jane Sweeney and her brother Tom Mortenson. Services are private.