Well, Gi, to be a perfectionist, iit is PI not PHI.
On a serious note now, I can say that Egyptologists and cranks alike agree that Egyptians measured out dimensions by using a rolling drum which involved the use of PI due to the drum being a cylinder. So, we know they knew about the properties of a circle. They also knew about the earth being a sphere, as they could measure the length of a shadow at the east and west border of the country at a given time and see the difference in angle and length. This gave them a pretty good measure of the diameter of the earth. The real problem was the clumsy way they used math. This inhibited all mathematicians until the use of Arabic numerals BTW.
K