Relative chemical dating
As a relative dating method, it can determine the relative age of specimens, but cannot provide a calendrical date unless the fluoride chronology is calibrated with an absolute dating method.
Bones are primarily composed of the mineral calcium hydroxy apatite.
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.
Archaeologists use many different techniques to determine the age of a particular artifact, site, or part of a site.
All dating methods have limitations and can be complicated by turbation, or mixing, of layers by human or natural actions.
A relative age is the age of a fossil organism, rock, or geologic feature or event defined relative to other organisms, rocks, or features or events rather than in terms of years.
Older specimens have higher fluoride contents than younger ones when burial conditions are identical.
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.
In such cases subjective element cannot be ruled out.
But, for a single culture site the method is quite reliable.