Every museum collection has its touchstones. Donald Judd’s shiny block ladders climbing the walls. Andy Warhol’s blown-out pastel prints of celebrities. Throw a dart in a modern art museum and you might hit a target painted by Jasper Johns. The canon is an assembly where museums rally for their contributions to our collective understanding of the history of modernism.

To say it’s a cozy corner is an understatement. A recent study of 18 major U.S. art museums finds that 85 percent of artists represented in their collections are white, and 87 percent are men. It’s a better story in modern collections, where (thanks to social progress plus the tireless work of contemporary curators) figures such as Ana Mendieta and Louise Bourgeois have been admitted into the fraternity. Lynda Benglis, David Hammons, and D.C.’s own Sam Gilliam are some of the newfound stars who once lived in the outer orbit, held at a bay for far too long by myopic museum leaders.

Then there are the true outliers. When a museum surveys a long-overlooked artist—someone who worked at a geographic, linguistic, or political remove from the prevailing post-war currents in America or Western Europe—it arrives like a breath of fresh air. Zilia Sánchez: Soy Isla, now on view at the Phillips Collection, is the first museum survey of an artist whose career spans nearly 70 years. It is better than refreshing: It is a canon course-correction.

The artist’s work flows through two different veins. One is drawing: In her early work especially, Sánchez uses line to break down figures and forms in space. Her other mode is something else: a form of painting over stretched canvas that’s been missing from the modernist conversation. Her work threads an unlikely needle between Dada and minimalism.

“Lunar blanco (White Moon)” (1964) is an example of a star that belongs in a lot more white-cube collections. The piece is a round painting on a plinth, a shaped canvas and pedestal that challenges the traditional boundaries of painting. Enclosed within the white dial is a concentric circle of faint blush acrylic. Two forms nearly protrude through the surface of the painting, giving it kinetic tension and a sloping surface. Imagine a fork with two tines poking a cloth coin. In the early ’60s, Sánchez began making these abstract paintings that combined soft shapes with hard edges and a mute palette.

Through a largely chronological presentation, Phillips curator Vesela Sretenović showcases three broad phases in Sánchez’s work. Her very earliest drawings, including pieces from a series called “Afrocubanos” from the late 1950s, combine sharp surrealist scribbles with broad spatial abstraction. “Lo que es de isla y piel (Belonging to Island and Skin)” (1958) could be a hard-edged geometric painting but for the spontaneous little satellite of inky arms and antennas squirming at the base of her atmospheric form. Another mode of Sánchez’s work, which Sretenović connects to time the artist spent traveling in Europe and a French abstract style called tachisme, could be a show of its own: “Tierra (The Earth)” (1959) and “Untitled (Agua)” (1961) are deep, gestural paintings in rich clay tones.

Sánchez, a Cuban artist who works today in Puerto Rico, is not a name viewers are likely to know coming into the show. Born in Havana in 1926, she enjoyed her first solo show as a painter in 1953, during the early years of the U.S.–backed Fulgencio Batista regime. Sánchez enjoyed a fast rise to prominence in the Havana scene over the revolutionary years. The artist participated in the fifth São Paulo Biennial in 1959, the year before she fled Fidel Castro’s rule for New York, where she quickly found her place among the Cuban community living in exile. 

In addition to her more than 60 paintings and works on paper, Soy Isla compiles pamphlets and journals that chronicle her life as an émigré and activist. These literary magazines echo back to the Dada period, when an earlier generation of artists incorporated inputs from across conflicts and continental divides to generate vital new recombinant forms of art. Sánchez’s early concretist drawings even look surrealist, although her work cooled into a smoother geometric abstraction in the 1970s. 

“Lunar V (Moon V)” (1973) is one of a series of diptych-style paintings produced by the artist over this decade. The painting appears to be a depiction of a round form split down the middle along the vertical. Where the the halves of the painting meets, the shaped canvases join as interlocking lips. “Construcción: Topología erotica (Construction: Erotic Topology)” (1973) features a similar set of labial forms, this time meeting across a horizontal plane. Later works, among them “Juana de Arco (Joan of Arc)” (1987), cross over from abstract to figurative depictions of yonic forms. Minimalism—made in the ‘60s, mostly by men, working at a clinical remove from the canvas—might appear to be the tag for Sánchez’s work. But the eroticism and indulgent artist’s hand apparent in her paintings distinguish her work from the pack.

One of the artist’s concepts was a series of relief paintings called “Módulos infinitos (Infinite Modules)” that could be built out forever. “Troyanas (Trojan Women)” (1967), an example of her modular paintings, features identical canvas forms shaped like breasts or birds’ heads. Aligned in a potentially endless row, these paintings summon the relentless Amazonian daughters of war. This work really does show Sánchez the minimalist at work, as it suggest an almost mechanical process for producing new paintings.

It is ultimately Sánchez’s deviations from minimalism that separate her from other Cuban artists who are enjoying renewed interest today, namely Carmen Herrera (who herself just enjoyed her first museum retrospective, at the Whitney Museum of American Art, in 2016). Sánchez’s work falls somewhere between Herrera’s pure hard-edged geometric painting and Wifredo Lam’s Afro-Cuban Surrealism—two strands that come together in congress in a single artwork at times, such as with “Lunar con tatuaje (Moon with Tattoo)” (1968).

Soy Isla takes on two challenges: placing Sánchez’s work in the context of her Cuban contemporaries, such as the collective known as Los Diez, and explaining where her work does and does not fit among better-known Western art movements. There is still work to be done on that score, through other focused exhibitions putting Sánchez in dialog with Lucio Fontana, Jo Baer, and dozens of her other peers. Modern museums should be making room on their walls now.

At the Phillips Collection through May 19.1600 21st St. NW. $12. (202) 387-2151. phillipscollection.org.