A characteristic which is essential for a fossil to be considered an effective index fossil is that it must be distinctive, unique and easily recognizable.
What is a fossil?
A fossil can be defined as the mineral impression or remains of both living and non-living organisms that are generally considered to be pre-historic in nature.
Similarly, an index fossil refers to a type of fossil that is typically useful for dating, identify geologic periods and comparing the strata in which it is found.
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