Absolute dating, the ability to attach a specific chronological date to an object or collection of objects, was a breakthrough for archaeologists.
Until the 20th century, with its multiple developments, only relative dates could be determined with any confidence.
Since the turn of the century, several methods to measure elapsed time have been discovered.
The first and simplest method of absolute dating is using objects with dates inscribed on them, such as coins, or objects associated with historical events or documents.
Written by some of the foremost experts in luminescence dating from around the world, this book takes a new approach.
It explains what luminescence can and can’t do, what and where to sample, types of measurements available and how to interpret and analyse ages once they are measured.
Like tail fins on a Cadillac, artifact styles and characteristics change over time, coming into fashion, then fading in popularity. The standard graphical result of seriation is a series of "battleship curves," which are horizontal bars representing percentages plotted on a vertical axis.
In other words, artifacts found in the upper layers of a site will have been deposited more recently than those found in the lower layers.
Cross-dating of sites, comparing geologic strata at one site with another location and extrapolating the relative ages in that manner, is still an important dating strategy used today, primarily when sites are far too old for absolute dates to have much meaning.
Stratigraphy is the oldest of the relative dating methods that archaeologists use to date things.
Stratigraphy is based on the law of superposition--like a layer cake, the lowest layers must have been formed first.