The Pyramid

Radiocarbon Dating Project

by

Norman Scherer

Copyright © 2004, Norman Scherer

Introduction

The Great Pyramid's mortar was sampled for "fragments of charred wood or other plant fibers" that could possibly be radiocarbon dated.¹ The results were supposed to settle the debate once and for all on the age of this structure and some of the other ones located in this area. The study was funded by the Association for Research and Enlightenment (ARE), an organization started by the American psychic Edgar Cayce. Edgar Cayce gave information that indicated a much older date for the construction of the Great Pyramid. It was to try to verify or refute this information that caused the ARE to fund this research with one of its former proponents taking the lead in the investigation, noted Egyptologist Mark Lehner. Let's look at the evidence that was gathered and see what logical conclusions can be drawn.

Gypsum Mortar

In the report that was issued of the results, it was noted that:

....gypsum mortar  was used to level, align and bond the stone blocks of some of the pyramids. This mortar was made by heating gypsum and small amounts of limestone in wood fires, and then mixing the anhydrous product with quartz sand and calcite to produce a substance that would harden when mixed with water and exposed to air (Lucas, 1974). In the manufacturing process small amounts of ash, charcoal, and other organic materials were added, probably unintentionally, to the mortar. Samples of carbonized materials from gypsum mortar ranged from a few milligrams to about 3 grams.²

The first question that arises, when reading the above excerpt, is 'how much gypsum did they need to make?' If you take into account all the stones that were used in the two biggest pyramids you start wondering about the amount of gypsum that was used. The picture below was used in the "construction date" article and it's worth looking at again to remind the reader of the enormous size of only one of these massive pyramids:

Apparently this pyramid (Khafre), along with the Great Pyramid, (which is even bigger) had gypsum mortar "slopped" on all these stones to "level, align and bond the stones".  From Mark Lehner's 1995-6 report, we read that,

The cores of the giant Giza Pyramids were built with great quantities of gypsum mortar slopped between the stones that the builders set with far less precision than the fine masonry of the outer casing.

My first question is, where did they get all the wood to make all these fires to heat the "great quantities" of gypsum mortar to slop on about a million stones?  Not much grows in the desert, so I'm wondering where the fuel source came from?

In a study done by Southern Illinois University at Edwardsville (SIUE) of the pyramid mortar, it was noted that:

The blocks [of the Great Pyramid] vary in size from 4000 lbs to 100,000 lbs. The weight of the blocks and the shape of the pyramid made mortar unimportant for bonding the blocks together in a continuous mass. Gravity and the design of the pyramid basically held the structure together.

....However, the mortar played a critical part in the construction of the pyramids. The key reason mortar appears to be used was to "butter" the joints and to reduce the friction as the blocks were maneuvered into place. A simple experiment used by the authors showed that the force to move a block is reduced by approximately one-half when gypsum mortar is used.

....Most of the mortars appear to be basically a processed gypsum that had traces of sand and limestone when mined. The gypsum has a small percentage of sand and limestone thus supporting the concept that the gypsum was used as processed. The sand and limestone were not added but were "contaminants" of the processed gypsum.

Gypsum is not used today as a mortar. It has relatively low strength and deteriorates in wet weather.....gypsum mortar would not be acceptable as a mortar in a wet environment. For Egyptian construction, especially in the desert area, when the pyramids were built, gypsum mortar would obviously work.

I think that the above statements are mutually exclusive. Gypsum mortar will only work in a desert, yet you need fire to heat it before it can be applied. What do you burn in a desert to make enough fire to make all this gypsum mortar? I can understand making small amounts of mortar. However, we are talking about some of the biggest stone structures in the world, encompassing perhaps a million individual blocks (when combining the amounts in the two largest pyramids). I cannot reconcile the amount of fuel needed in a desert environment to heat all the gypsum needed "to butter the joints" of a million or more huge limestone blocks in the almost incomprehensible time frame allotted for their construction. The fact remains however, that the mortar is there. Is there perhaps another scenario to explain the presence of vast quantities of gypsum mortar on the core masonry?

Radiocarbon Dating Results

The table below summarizes the results found from radiocarbon dating items found embedded in the mortar of the Great Pyramid: ³

In analyzing the above table, two things are immediately apparent. The dates are hundreds of years older than what was generally accepted, and the range of dates is almost a 1000 years. This seems odd due to the fact that it is currently accepted that the Great Pyramid was built over a 20 year period. Why such a large range of dates? This also caused some consternation with Mark Lehner as he admitted in an interview with the ARE magazine Venture Inward in the May-June 1986 issue:

.....you can summarize the results by saying our dates are 400 to 450 years too early for the Old Kingdom Pyramids, especially those of the Fourth Dynasty....Now this is really radical....I mean it'll make a big stink. The Giza pyramid is 400 years older than Egyptologists believe.

It is also apparent that they are nowhere near the dates that Edgar Cayce channeled in reading 5748-6, which indicates that the Great Pyramid was built from 10,490-10,390BC:

Q-5. What was the date of the actual beginning and ending of the construction of the Great Pyramid?

A-5. Was one hundred years in construction. Begun and completed in the period of Araaraart's time, with Hermes and Ra.

Q-6. What was the date B.C. of that period?

A-6. 10,490 to 10,390 before the Prince entered into Egypt.

So who is right? If Cayce is right then something is very wrong with the radiocarbon dating method which is highly unlikely, or the table above is correct and Cayce was off by 7000 years which also seems unlikely. Is there another explanation?

The Casing Stones

It becomes apparent that an important consideration in this issue is, when were the white Turah limestone casing stones removed from the pyramids? I had always assumed that the Great Pyramid was completely intact until a certain Sultan of Hasan started removing the hard, white, marble-like casing stones to build a mosque in 1356AD. I was surprised to learn that this was not so. In a Nova on-line interview with Egyptologist Mark Lehner he relates the following:

(posted February 7, 1997)

Question:

How did the pyramid lose 9.5 m off the top?
Anonymous
 

Response:

Mark Lehner, Egyptologist: Well, this is the Great Pyramid of Khufu. The top-most part was lost because, over time, the pyramid outer casing was stripped for stone to use it in building elsewhere. What we see of the pyramids today is the stepped core stone which is a coarser limestone than that which was used for the outer casing. On the upper fourth or fifth of Khafre's Pyramid the casing is still preserved. We have evidence that the stripping of the pyramids' fine outer casing began as early as the New Kingdom in ancient Egypt - the era of Tutankhamen, when the pyramids were already 1200 years old, or more! The removal of the casing of the Giza Pyramids, therefore, went on from the 12th century B.C. to the 12th Century A.D. when the Arab historian, Abd al-Latif al-Baghdadi, visited Egypt (about 1196 A.D.) and reported that Karakoush, working for the Egyptian ruler, began to quarry the smaller pyramids at Giza for building stone. The fact that the casing still hangs on the upper part of Khafre's Pyramid indicates that those who stripped the fine limestone off the pyramid casings started from bottom and progressed to top. We are not sure exactly when the stripping of the casing of the Khufu Pyramid reached the top, but in the process the upper courses were completely removed, probably because they were almost entirely composed of the finer limestone from across the Nile Valley at Turah as opposed to the cruder limestone from nearby quarries at Giza, which makes up the bulk of the core stone. As they got to the top, the builders needed that finer limestone for greater control in bringing the sharp diagonals to the point of the apex.
 

If Egyptologists have evidence that the casing stones were removed as early as the 12th century BC, then there is the possibility that this process may have begun at an even earlier date, but we just don't have the evidence for it. If this is so, it may explain why the radiocarbon dates are older than were expected. If the Great Pyramid was built in the 10,500BC era as channeled by Edgar Cayce, then the mortar sample dates could possibly show, not when the casing blocks were put into place, but when they were removed. Or more accurately, they may only show that the casing stones were removed sometime prior to the mortar application.  The radiocarbon date of 3809BC on the top of the Great Pyramid is strong evidence that the structure was already finished by that date. Most of the other dates cluster around the 3100-2800BC timeframe. This proves then that the mortar was not used in the construction phase of the pyramid because the pyramid was already finished by 3809BC. The 300 year time span of 3100-2800BC, which dates the mortar found on the pyramid, proves that the casing stones were already removed by that timeframe. There can be no other conclusion from the data presented. If the mortar found throughout the pyramid is dated from 3100-2800BC and yet the pyramid was already finished by 3809BC, what other conclusion can you draw? The casing stones must have been removed prior to 3100BC.

Also, as pointed out in the SIUE study, gypsum mortar could only have been applied in a dry environment because it is ineffective in a wet one. Therefore, the dates begin around 3100BC when the climate in that region started to become much drier and gypsum mortar would then have become an effective mortar to use:

Lawton and Ogilvie-Herald (page 313) agree with me that the current arid climatic regime of the Giza Plateau began approximately in the middle of the third millennium B.C. and there were various periods of relatively heavy rainfall from about 10,000 or 8,000 B.C. up until the onset of the predominant aridity that has existed in the area for the last 4500 years or so.

Sporadic heavy rains and the resulting flash floods (due to the inability of the rain to penetrate and soak into the land's surface and thus it runs off and collects in valleys, wadis, and other depressions) commonly found in arid regions do have tremendous potential to move loose debris and even cause serious erosion. However, in my opinion as a geologist, the nature and especially degree of weathering seen in the Sphinx enclosure and on the body of the Sphinx itself, is incompatible with sporadic flash floods since dynastic times. Even if occasional heavy rains occur on the Giza Plateau, the fact remains that currently on average only about an inch of rain each year occurs in the region (25 to 29 mm annually).⁴

Conclusions

The theory outlined above explains many of the anomolies that were found in the radiocarbon dating of the Great Pyramid's mortar:

1. From the SIUE study we find that the mortar was unimportant for bonding the blocks together so it must have been applied for some other reason.

2. Radiocarbon dates of the Great Pyramid begin at 3809BC by some charcoal which was found on TOP of the Great Pyramid. This proves that the pyramid was already finished by that time. So how could there be mortar dating from a later three hundred year period if the casing stones were already in place by 3809BC? It's impossible. You can't have a pyramid finished at a date that precedes the dating of mortar that is supposedly underneath the casing stones. Therefore the casing stones must have been removed before 3100BC. And so the dating of this mortar proves nothing except that it had to have been applied long after the pyramid was constructed.

3. Gypsum mortar is only effective in a dry environment which the Giza area has experienced only since around 2500BC. Therefore it would have been impossible to apply the mortar much earlier than this because it wouldn't have even worked. This explains why the cluster of dates begins around 3100BC. There would have been no reason to apply gypsum mortar any sooner because the environment at Giza would have been too wet for it to be effective.

What these facts seem to suggest, is the possibility that the Giza pyramids' outer casing stones may have begun to be removed long ago in antiquity. The Old Kingdom Pharoahs may have decided to embark on a massive repair project that entailed "slopping" gypsum mortar to fill in many of the gaps of the inner limestone core to keep the structure sealed. This process may have occurred, on and off, over many centuries,  culminating in Khufu's finishing of the repair of the Great Pyramid.

 ¹  Chronologies in the Near East (O. Aurenche, J. Evin, and F. Hours, eds.; BAR International Series 379 (ii); 1987; p. 587.

 ²  Ibid.

 ³  Ibid. p. 606

 ⁴ Comments by Robert M. Schoch on the Geological Analysis of Ian Lawton and Chris Ogilvie-Herald

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