During and after an excavation, an archaeologist confronts a bewildering collection of artifacts, drawings, and photographs to decipher and relate to one another.
Using both relative and absolute dating methods, an archaeologist can often place a site within a larger chronological framework.
A set of criteria for acceptable dates is proposed.
Luminescence dating dates crystalline materials, such as quartz or feldspar, to the last time they were exposed to sufficient heat or sunlight.
In relative soil dating, archaeologists follow two general principles known as refers to the concept that all the soil below a solid, undisturbed layer dates before that layer (see Figure 3).
Relative dating of a site's stratigraphy often depends on the absolute dating of excavated materials and artifacts.
Archaeologists sometimes use thermoluminescence dating to establish the age of pottery.
This technique is similar to carbon 14 dating in that, like organic substances, pottery contains small amounts of radioactive elements that decay at known and steady rates.
The relatively short-lived C taken into organic matter is also slightly variable. However, under about 20,000 years the results can be compared with dendrochronology, based on tree rings.
In 1960, he was awarded the Nobel Prize in Chemistry for this work.
He first demonstrated the accuracy of radiocarbon dating by accurately estimating the age of wood from an ancient Egyptian royal barge of which the age was known from historical documents.
The 1885 coin in Layer E establishes that Layer E dates from on or after 1885.
It follows that the pottery fragment in Layer D and the bottle cap in Layer B likely date from or after 1885 as well.