Everything around us is made of chemical compounds that have testable and identifying characteristics, allowing them to be classified, and their age determined.This also applies to rocks, minerals, and derivative materials (such as sediments and soil).Cultural seriations are based on typologies, in which artifacts that are numerous across a wide variety of sites and over time, like pottery or stone tools.If archaeologists know how pottery styles, glazes, and techniques have changed over time they can date sites based on the ratio of different kinds of pottery.
It does not, however, allow one to independently assign an accurate estimation of the age of an object as expressed in years.
ugs / online publications / survey notes / glad you asked / rock ages How Do Geologists Know How Old a Rock Is?
by Mark Milligan Geologists generally know the age of a rock by determining the age of the group of rocks, or formation, that it is found in.
The most common relative dating method is stratigraphy.
Other methods include fluorine dating, nitrogen dating, association with bones of extinct fauna, association with certain pollen profiles, association with geological features such as beaches, terraces and river meanders, and the establishment of cultural seriations.