Collagen content dating
Usually, dilute HCl (10% conc.) is used in this treatment.It is added to the sample in a beaker which is placed on a hot plate and heated until slowly boiling.
A glass filter is placed at the bottom of the funnel and dampened with distilled water (dist. Afterwards, the sample is placed on top of the filter paper and a number of litres of distilled water poured in and drawn through the sample by the vacuum effect.
Sodium hydroxide (Na OH) treatment is usually associated with the removal of humic acid contamination from soils, wood, charcoal and peat samples.
Humic acids are the mobile decay products of biological materials deposited in the vicinity of the sample matrix.
A soxhlet extractor is the most common apparatus used in the extraction method.
This apparatus continually recycles the solvents being used so that they do not have to be replaced.