Courtesy Geopolymer Institute

One of the great things about writing a nonfiction book is doing the research. You pick up all sorts of intriguing bits and pieces. And one of the not-so-great things about writing a nonfiction book is that you never have enough space to use everything you’ve uncovered.

Maybe that’s a good thing for the reader!

My upcoming nonfiction book is called Rope — How a Bundle of Twisted Fibers Became the Backbone of Civilization, to be published by St. Martin’s Press in spring 2025. Rope explores the history, present uses and possible future applications of rope. It’s great story, you’ll love it.

One of the major uses for rope in ancient times was for hauling stuff around. And one of the biggest examples of hauling stuff around was the building of the pyramids in ancient Egypt. We tend to assume (for good reason!) that the pyramids were built by piling up limestone blocks.

But what if they weren’t?  

There’s the idea that building the monument was not mechanical but chemical — that the blocks were not hewn from limestone but were cast from a manmade concrete-type mixture. Professor Michel W. Barsoum from the Department of Materials Science and Engineering at Drexel University, an expert in ceramics, is a proponent of this theory, which is based on earlier work by French materials science professor Joseph Davidovits, who headed the Geopolymer Institute in San Quentin, France. Barsoum and Davidovits claim that the stones are not natural limestone but a form of concrete made of limestone, clay, lime and water. The mixture was made on the ground and then slopped into molds up on the pyramid.

According to this theory, there was no need to drag bulky stones up a ramp, straight or spiral, since the blocks were cast in place. Although the mixture still needed to be carried up, it could have been done in small containers without the problem of maneuvering stone blocks into place on the increasingly smaller working area of the pyramid’s upper levels. Prof. Davidovits and a crew of workers dressed in traditional Fourth Dynasty garb, including head scarves (see image above), made videos of them mixing and forming several blocks of this material in 2003 at the Geopolymer Institute.

Could the pyramids have been built this way? What’s your theory on how those manmade mountains rose? 

More info: Geopolymer Institute “Are Pyramids Made Out of Concrete?” April 9, 2006 https://www.geopolymer.org/archaeology/pyramids/are-pyramids-made-out-of-concrete-1/