The Sahara desert is from over-farming by the ancient Egyptians 30,000 years ago, and the great pyramid is a fission powered ammonia generator. The arc of the covenant was a stolen nuclear fission core, and the only reason humans think gold is valuable is it was written into our DNA by the Nephilim so we would mine it out of the ground for their various practical usages such as shielding for advanced propulsion and weapons. They left the earth to us after we had mined the majority of the gold.