Method of dating
It is nearly always association with other phenomena that gives a first clue as to the use, the age and chronological attribution of a potential datum, but age at least may sometimes be inferred from position in a geological deposit or a layer of peat.
Once a type has been classified by the aid of its context further specimen of the same type, even when found in isolation, can be assigned their place in terms of dates.
In cases where the samples have been analyzed in full age profiles, a horizontal, platform at the beginning of the profile is expected to show the same minimal gradient, if at all (Cf. ) When the first CO2 fractions coincide in a series of three or more samples from the same building unit.
This dating method is also known as Archaeological Dating or Historical Chronology. These methods were relied on especially prior to the introduction of scientific methods of dating.
C were found in a late context (Period V) at Harappa. By noting the association of these beads it has been possible to trace a archaeological datum line across Indian sub-continent and Mesopotamia.
The samples are separated chemically into several consecutive CO2 fractions, which are all dated separately. Chemical separation of mortar into separate CO2 fractions The effects of contamination will be evident from the age profile created by the dated CO2 fractions.According to this method, the upper deposits are younger and the lower deposits are older.Basing on this principle, the cultural assemblages found in different layers can be assigned a chronological personality. In practice it is found that the mounds are disturbed9 by all sorts of pits and dumps.The calcium oxide is slaked with water and converted into calcium hydroxide (slaked lime, Ca(OH)2).It is then mixed with water and an aggregate (usually sand, gravel or volcanic pyroclastic materials) to form mortar.