Archaeomagnetic dating is the study and interpretation of the signatures of the Earth's magnetic field at past times recorded in archaeological materials. These paleomagnetic signatures are fixed when ferromagnetic materials such as magnetite cool below the Curie point , freezing the magnetic moment of the material in the direction of the local magnetic field at that time. The direction and magnitude of the magnetic field of the Earth at a particular location varies with time , and can be used to constrain the age of materials. In conjunction with techniques such as radiometric dating , the technique can be used to construct and calibrate the geomagnetic polarity time scale. This is one of the dating methodologies used for sites within the last 10, years. Thellier in the s  and the increased sensitivity of SQUID magnetometers has greatly promoted its use.
Archeomagnetic and Radiocarbon Dating – The Cañada Alamosa Project
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Firstly, it is purely coincidental that I study in Bradford West Yorkshire and am coming to take samples at the Bradford Kaims. As an archaeomagnetist, and we are pretty few and far between, it is always amazing the variety of sites that you get to see and work on. Having parachuted into the Bradford Kaims trenches for the second time, this site is no exception in its wonder. Placed at the edge of a fen, the variety of soil and sediment types on site is impressive! This offers the perfect opportunity for archaeomagnetic studies.
Another way naturalists look to estimate the age of rocks besides radiometric inquiries we find the occasional use of both thermoluminescence and optically stimulated luminescence dating. Thermoluminescence dating is performed by heating specific minerals to a point where they release the photons elementary particles related to light and electromagnetism contained within. The mineral sample is then struck with radiation or light, each of which cause the sample to capture a fresh load of photons, and afterwards the sample is heated yet again, releasing the fresh photonic load.