His result was in close agreement with his estimate of the age of the earth.
The solar estimate was based on the idea that the energy supply for the solar radioactive flux is gravitational contraction.
Even when the absolute dates are available, we have to supplement the information with relative dating.
The various methods of relative dating are; This method depends on the common observation that the height of the habitational area increases as the people continue to live at the same place.
The requirement of identical burial conditions means that fluoride dating works best when it is applied within a single site with little variation in soil chemistry.
Many different techniques can be used to measure bone fluoride content, but measurement by ion selective electrode is the easiest and simplest method available today.
When a new fossil is discovered, geologists assign a date for when they think the plant or animal lived.
They normally use radiometric dating methods to date the fossil, and many promote these methods as being accurate.
Older specimens have higher fluoride contents than younger ones when burial conditions are identical.Other factors and basic assumptions must also be considered.Of course, Kelvin formed his estimates of the age of the Sun without the knowledge of fusion as the true energy source of the Sun.The resulting fluor-apatite is more stable than the original form, thus the fluoride content of a bone will increase over time if it is exposed to a solution containing fluoride ions.Fluoride ions are present in trace amounts in most soils and groundwaters.