The 13 rays of red and gold on the top half of the flag represent both the 13 original colonies of the Union, and the rays of the Western setting sun. Red and gold were also the colors carried by Coronado’s Spanish expedition in search of the Seven Cities of Cibola in 1540. The bottom half of the flag has the same Liberty blue as the United States flag. Since Arizona was the largest producer of copper in the nation, a copper star was placed in the flag’s center.