We were playing tag in a large wheat field on top of the hill, when I observed what I thought was a clear plastic kite flying in the sky to our northwest. My first instinct was that it was a large kite that had broken loose from its string, but then upon starring at it, it began to move against the wind and started radiating a colorful swirl withing its exact diamond shaped structure. The best description of the multi-colors i was observing was comparing it to spilt gasoline on top of water. It was as brightly colored as a rainbow but the colors swirlled in a random pattern within the diamond. After a few seconds or so, I realized the object was probably not solid and I wanted someone else to verify what I was seeing so I hollered to my cousin and my brother who were in the field to look. They ran to me and I pointed out the object. We all stood in silence for a few seconds, then looked at each other. The object appeared to be about 100 yds away and maybe 100' off the ground. I used a line off power poles to gauge the height and distance. We decided to chase it for some unknown reason. As we approached the object it went higher in the sky and randomly and quickly moved in numerous directions. We wondered why it was moving away from us. As we stopped to catch our breath it began to grow in size or come closer, couldn't tell which ,then it shot north at the speed of a lightning bolt and disappeard. We ran back to the house to tell our parents, but they all laughed. The strangest thing about viewing this object was that it seemed semi-clear but had a perfect diamond shape. Seems impossible. It was not a "sun-dog", I have seen many of these around the sun. The object was viewed during a thunderstorm while the sky was full of lots of clouds and the sun was not directly visible. My best guess as to the size of the object was that it was about 6' wide by 6' tall. After telling our parents and calming down we went back to the hilltop about 30 minutes later to look for the object with some more cousins, but we saw nothing. My cousin and brother all agree about the size, shape, color, speed, and distance of the oject. We have not been able to explain this observation at all.