Most scientific dating methods which have found a place in archaeology are based on physical principles. Chemical analyses are sometimes useful in establishing the earliest possible date on which a particular object might have been fabricated. The following methods are elucidated: radiocarbon dating, potassium-argon, uranium-thorium, dating possibilities for bone material (radiocarbon and collagen content, amino-acid content, amino-acid conversion, manganese content, transmission of ultrasound, fluoride content), dating of pottery by thermoluminescence, and of glass by fission track, magnetic dating of objects made of burnt clay, obsidian dating from the effloresced crust, and dendrochronology of wood. -- AATA