Matthew Marks Gallery is currently celebrating the 90th birthday of American artist Ellsworth Kelly with an exhibition aptly entitled At Ninety, which spans all three of the gallery’s Chlesea spaces. For over 60 years, Kelly has expressed his own style of minimalist art through painting, sculpting and print-making, often focusing on simple forms and monochromatic colors. In the gallery on W. 24th, the space is dominated by four large relief paintings from 2011, respectively consisting of a red, blue, yellow or green shaped panel overlapping a white canvas. Each work on its own examines the simplicity of form and color, but together they create an interplay of similarities and differences that enhances the visual experience. In addition to the color pieces, there are several all white works, which vary from a flat shape to white-on-white relief. At Ninety runs until June 29.