Radiocarbon dating religion
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.
There are people who are experts in all these different periods of pottery or Egyptian ceramics.
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.
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.
So in effect, you're counting the carbon-14 in an organic specimen.