Fluorine dating chronometric dating technique
Astronomical data have been applied in the study of geological ice ages by calculating the curves for major fluctuation of solar radiation.Consequently, the chronology worked out for the geological deposits helped in dating the prehistoric tools found in these deposits. There are certain antiquities and potteries which by themselves have acquired a dating value.The types and forms or shape of these pots and also the antiquities under go evolutionary changes in cource of time, It is further assumed that all living animals derive body material from the plant kingdom, and also exhibit the same proportion of C-14 material.Therefore as soon as the organism dies no further radiocarbon is added.This closely agrees with the fact that the seals from Indus Valley style from Ur, Kish and Tell Asmar and other sites fall within the range of 2500-1500 B. When a group or type of objects are found together under circumstances suggesting contemporanity they are said to be associated.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.Even when the absolute dates are available, we have to supplement the information with relative dating.
Association in simplicity can be illustrated by an example, at the port of Arikamedu near Pondicherry.
Whenever and where ever such antiquities are found, associated finds are automatically dated.
For example Mauryan terracottas, Roman amphorae, Harappan pottery, NBP , PGW,etc.
The quantity of the C-14 remaining is measured by counting the beta radiation emitted per minute per gram of material.
Modern C-14 emits about 15 counts per minute per gram, whereas Carbon-14 which is 5700 years old, emits about 7.5 counts per minute per gram.