NEW YORK, NY.- Martha Diamond, a painter’s painter who captured the endlessly changing face of New York’s buildings, streets and light-filled vistas with deceptively simple expanses of color, died Saturday after a long illness. She was 79.

Her death was confirmed by the Martha Diamond Trust.

Diamond’s work occupied a unique point at the intersection of several approaches. She handled paint with the gestural elan of a materials-focused abstract expressionist. Her stark but vibrant depictions of her native city, in which an eight- or 10-story edifice on a busy street might be reduced to a liquid gray rectangle against an undifferentiated orange sky, recalled mid-period Piet Mondrian, before that Dutch pioneer fully abandoned representational painting.

So as never to do anything rote, she painted with her nondominant left hand. And in her deep commitment to the particulars of her own milieu — she often painted the view from her light-filled Bowery loft — she was like Jane Freilicher and other New York School mentors and friends.

Personally, she was a point of intersection, too, maintaining long-standing friendships with poets, gallerists and painters; teaching generations of students; and holding down her small but critical place in the development of American painting with unwavering devotion.

But if her artistic life was characterized by its proliferation of influences and interests, her art itself was largely defined by what it excluded.

In her 1988 painting “World Trade,” one of three works included in the Whitney Museum of American Art’s 1989 Biennial, two thick, sooty bars hang down the middle of a 6-foot-tall canvas. Their color, which hovers somewhere between brown and pink, is denser at their top and bottom edges. The distinct, wood-grainlike texture of long, visible brushstrokes at once captures the buildings’ famous vertical lines and, by exposing slivers of unpainted white linen, suggests a dazzling glare. And apart from a few smudgy red and blue lines behind the buildings, and some diagonal strokes in front that might be clouds, that’s it.

“People who look at the painting have an idea of what the World Trade Center is, and here’s a painting called ‘World Trade Center,’” Diamond explained in a video interview posted by Magenta Plains Gallery, which briefly represented her. “What’s interesting is how much is left out while you know exactly what it is.”

What she left out, paradoxically, made what remained inexpressibly richer. Viewers could immediately grasp the essence of the subject without getting lost in extraneous details.

“Recognizability or familiarity leads the viewer to look for expected detail,” she told poet Bill Berkson for a 1990 Artforum article. “For the most part the details are not there so you look harder at the paint and the painting. You begin to distinguish between paint, performance, image, idea, expectation and you.”

Martha Bonnie Diamond was born May 1, 1944, in the New York City borough of Manhattan to Norman Diamond, an internist, and Lillian (Levine) Diamond, a homemaker. She was raised in Hollis Hills, in Queens, and in Stuyvesant Town, in Manhattan. She is survived by her sisters, Miriam Diamond-Barber and Elaine Diamond Ford, and a brother, Michael.

Diamond began drawing as a child and often accompanied her father to hospital rounds near the Central Park Conservatory Garden, remaining awestruck, many decades later, by the looming Manhattan skyline that appeared as they drove across the Queensboro Bridge.

She earned a Bachelor of Arts in art and art history from Carleton College in Northfield, Minnesota, in 1964. There she befriended artist Donna Dennis and poet and art critic Peter Schjeldahl.

After a postgraduation trip to Paris with Dennis, Diamond returned to New York, where she went to the movies with poet Ted Berrigan, spent time with poet Ron Padgett and explored the city’s neighborhoods with Schjeldahl.

Poet Anne Waldman, another friend, remembered the “passion of becoming artists together.”

“When you feel it with people who have this conviction already,” she said in an interview, “it’s very much in them, and I felt that with Peter at an early age, and with Donna and with Martha.”

In 1966, Diamond got a job in the film department at the Museum of Modern Art. “I learned a lot working there, helping with different openings,” she told Artforum in 2021. “I would have meals in the gardens, and a poet would bring drugs, and that was great.”

Diamond found her loft on the Bowery, below Houston Street, in 1969 and remained there for the rest of her life. In 1970, painter Joan Mitchell visited her there and encouraged her to move her paintings, which she had been making flat on the floor, onto a wall.

In the years that followed, Diamond led printmaking workshops in New York City public schools as part of the Solomon R. Guggenheim Museum’s Learning Through Art program and taught at Harvard University, Yale University, the Goddard Riverside Community Center in New York and the Skowhegan School of Painting & Sculpture in Madison, Maine, on whose board of governors she also sat for 36 years.

Her first solo show was with Brooke Alexander Gallery in 1976, and it was there, in 1982, that she debuted her cityscape paintings. She later joined the Robert Miller Gallery.

Diamond had her successes, appearing in the Whitney’s influential 1984 “MetaManhattan” show as well as in its 1989 Biennial, winning a National Endowment for the Arts fellowship in 1980 and an Academy Award for Art from the American Academy of Arts and Letters in 2001. Her work has been acquired by the Art Institute of Chicago, the Brooklyn Museum, the Whitney, the Museum of Modern Art, the Guggenheim and others.

But her recognition was never quite in proportion to the significance of her work.

“There was that sort of early experience of feeling not the same amount of interest in our work as in the male artists of the circle,” Dennis said in an interview. “In her last years, she was getting the just attention, but her work could have gotten that earlier. It was just as strong 30 years ago, 40 years ago.”

The David Kordansky Gallery, which recently began representing Diamond, will present her work in a solo show in Los Angeles this spring. A traveling survey exhibition, to appear at the Colby College Museum of Art in Maine and at the Aldrich Contemporary Art Museum in Connecticut, is also planned for this year. And she has been championed by prominent painters such as Alex Katz, who said her work “represents the spirit of optimism of the 1960s,” and David Salle, who curated her work in group shows at Skarstedt Gallery and the Hill Foundation, both in New York.

“Martha Diamond was a terrific painter who didn’t fit the fashion of the times,” Salle said in a statement. “She didn’t appear to have a big ego, so people felt justified in thinking she was minor. The neglect didn’t make her happy, but it didn’t stop her. Posthumous fame will now be hers. I hope she enjoys it.”

This article originally appeared in The New York Times.