Radiocarbon dating in memphis egypt
So how do you date the pyramids, because they're made out of stone and mortar?Well, in the 1980s when I was crawling around on the pyramids, as I used to like to do and still do, I noticed that contrary to what many guides tell people, even the stones of the Great Pyramid of Khufu are put together with great quantities of mortar. A pyramid is basically, most basically, two separate constructions: it's an outer shell of very fine polished limestone with great accuracy in its joints, but most of that's missing; and the other construction is the inner core, which filled in this shell.We're dealing with basically the entirety of Egyptology and Egyptian archaeology.NOVA: Can you give us an example of a single aspect of material culture, from ancient Egypt that you might use as a starting point for dating the pyramids? All the pottery you find at Giza looks like the pottery of the time of Khufu, Khafre, and Menkaure, the kings who built these pyramids in what we call the Fourth Dynasty, the Old Kingdom.We study the pottery and how it changes over the broad sweep, some 3,000 years.There are people who are experts in all these different periods of pottery or Egyptian ceramics.And as you say, you need organic material in order to do carbon-14 dating, because all living creatures, every living thing takes in carbon-14 during its lifetime, and stops taking in carbon-14 when it dies.
So we're not dealing with any one foothold of factual knowledge at Giza itself.So in effect, you're counting the carbon-14 in an organic specimen.And by virtue of the rate of disintegration of carbon-14 atoms and the amount of carbon-14 in a sample, you can know how old it is.So to bring it down to a level that almost anybody can understand, if, for example, you were digging around the base of the Empire State Building, assuming that it was a ruin and the streets around it in Manhattan were filled with dirt, and you started finding ceramics that were characteristic of the Elizabethan era or say the Colonial period here in the United States, that would be one thing.But if you started finding the Styrofoam cups and the plastic utensils of the nearby delicatessen, then you would know by virtue of their position in the overall material culture of the 20th century that that's probably a good date for the Empire State Building.
So it's hard to give a succinct answer to that question, because we date things in archaeology on the basis of its context and a broad mass of information and material culture—things that were used by people, styles, and so on.