Nevelson continued to utilize wood in her sculptures, but also experimented with other materials such as aluminum, plastic and metal. "Black Zag X" from 1969, in the collection of the Honolulu Museum of Art is an example of the artist's all-black assemblages incorporating the plastic, Formica. In the fall of 1969, she was commissioned by Princeton University to create her first outdoor sculpture. After completion of her first outdoor sculptures, Nevelson stated: "Remember, I was in my early seventies when I came into monumental outdoor sculpture ... I had been through the enclosures of wood. I had been through the shadows. I had been through the enclosures and come out into the open." Nevelson also praised new materials like plexiglas and cor-ten steel, which she described as a "blessing". She embraced the idea of her works being able to withstand climate change and the freedom in moving beyond limitations in size. These public artworks were created by the Lippincott Foundry. Nevelson's public art commissions were a monetary success, but art historian Brooke Kamin Rapaport states that these pieces were not Nevelson's strongest works, and that Nevelson's "intuitive gesture" is not evident in the large steel works.