Αιγυπτιακό τσιμέντο απο γεωπολυμερή (4500πχ)

Are Pyramids Made Out of Concrete? (1)

http://www.geopolymer.org/archaeology/pyramids/are-pyramids-made-out-of-concrete-1

Pyramids (2) The evidences

http://www.geopolymer.org/archaeology/pyramids/pyramids-2-the-evidences

Pyramids (3) The formula, the invention of stone

http://www.geopolymer.org/archaeology/pyramids/pyramids-3-the-formula-the-invention-of-stone

Pyramids (4) Videos and download

http://www.geopolymer.org/archaeology/pyramids/pyramids-4-videos-download-chapter-1