Luminescence dating is particularly appropriate when radiocarbon dating is not possible (either where no suitable material is available or for ages beyond the radiocarbon age limit) or for applications affected by radiocarbon plateau effects (e.g.
post 1700 AD, early Iron Age contexts, late glacial timescales) and when the relationship between the organic materials and the archaeological context is uncertain.
As a result, all of the argon-40 in a volcanic rock sample is assumed to date from that time.
When a fossil is sandwiched between two such volcanic deposits, their potassium-argon dates provide a minimum and maximum age.
Such contamination can occur if a sample is exposed to carbon compounds in exhaust gasses produced by.