Very few artifacts recovered from an archeological site can be absolutely dated. Archeologists use several methods to establish absolute chronology including radiocarbon dating, obsidian hydration, thermoluminescence, dendrochronology, historical records, mean ceramic dating, and pipe stem dating.

What are the two methods scientists use to date artifacts?

While radiocarbon dating is useful only for materials that were once alive, scientists can use uranium-thorium-lead dating to measure the age of objects such as rocks. In this method, scientists measure the quantity of a variety of different radioactive isotopes, all of which decay into stable forms of lead.

What evidence do archaeologists look for?

A team of archaeologists will walk in straight lines back and forth across the study area. As they walk, they look for evidence of past human activity, including walls or foundations, artifacts, or color changes in the soil that may indicate features.