Morris is widely recognized for his sculptures that explore themes related to archaeology, anthropology, and the natural world. These subjects are united by the artist’s interest in myth and ancient history, and his understanding of nature. Morris is an experienced hunter and outdoorsman, and these activities are reflected in his art work. Petroglyphic Urn features a painting in glass powders that is inspired by Paleolithic cave art. The powders are arranged on a steel plate, heated, and then picked up onto the vessel during the blowing process. The process is challenging, and Morris is the only artist who can pick up such a large and complex drawing. The vessel is one of three that Morris made of this type, which features an incalmo rim of aventurine glass.