Dating differential mowatt dating
The samples most often given solvent pretreatments such as this are wood, soil organics, peat and charcoal, from specific environments.
A variety of solvents may be used in the extraction process, depending on the type of material and the contaminants present.
HCl acid washing is usually applied to samples destined for combustion.
Because HCl reacts with carbonate to produce CO2, its use in pretreatment work is restricted to non-carbonate samples.
The former may be kept for dating purposes by being acidified, rinsed and dried in an oven.Once the p H level is reduced, two sample fractions are left; an acid insoluble fraction and an acid soluble fraction.The soluble fraction should contain the carbonate contaminants and as such is seldom used for dating purposes, except when there is a need to know the age and nature of the contamination.As the pressure increases in the sample tube, the solvents are gradually deposited back into the original flask, whereupon the process is repeated.The contaminants are collected in the flask and either dated, stored for analysis, or discarded.