Grain A macroscopic sample of a crystalline mineral will generally consist of multiple conjoined crystals of varying shapes and sizes.

Each of these crystals, within which the atoms are arranged on a single regular lattice, is termed a grain Haematite An antiferromagnetic mineral, but due to slightly imperfect antiparallelism of the magnetised sublattices it exhibits a weak ferromagnetism.

archaeomagnetic dating range-73

Geomagnetic reversal The phenomenon where the direction of the geomagnetic field appears to have reversed so that the magnetic north pole exchanges places with the magnetic south pole.

The time between geomagnetic reversals is termed chron.

The critical temperature is specific to the sample in question and is related to the Curie temperature of the magnetic mineral it contains.

Dipole field The Earth's magnetic field which resembles the field of a magnet placed at the centre of the Earth.

The premise of Bayesian statistics is to incorporate prior knowledge, along with a given set of current observations, in order to make statistical inferences.

Coercivity spectrum A variety of grain sizes and shapes exist in a sample or specimen.

Antiferromagnetism A form of ferromagnetism where the crystalline material contains two oppositely and equally magnetised sublattices so that the net magnetism will be zero.

If the two sublattices are not magnetised in exactly opposite directions, a weak magnetism can be created and is referred to as canted antiferromagntism.

An example of a canted antiferromagnetic mineral is haematite.