In 1952, he went to Europe, also on the G.I. Bill. to study at the Académie de la Grande Chaumière. He became part of a group of African-American artists and writers who found, in Paris, inspiration and respite from discrimination that included Beauford Delaney, James Baldwin and Haywood Bill Rivers. But his friends also included white artists like Joan Mitchell, Sam Francis, Al Held and George Sugarman.

Mr. Clark arrived in Paris working in a figurative style, but within a year developed a Cubist-inflected style of abstraction dotted with bright colors that reflected de Staël’s influence.

As he had at the Art Institute, he conducted his education primarily by studying painting in museums, especially the Louvre, starting with Cézanne, although his palette also had a Renaissance lightness (a strong pink and a medium blue were favored hues).

In Paris he showed in several prestigious surveys, including the annual Salon d’Automne, and had his first solo shows at Galerie R. Creuze in 1955 and ’56, the year he returned to New York.

There he joined the exploding 10th Street art scene in Greenwich Village, helping to found Brata, an influential artists’ cooperative , in 1957.

That year, he exhibited a shaped painting in its Christmas group show that was closely studied by other artists. Shaped canvases would become an important hallmark of Minimalist painting in the 1960s. At the time, Mr. Clark started using elliptical paintings because he felt the shape was truer to the human field of vision.