Most scientists today believe that life has existed on the earth for billions of years.This belief in long ages for the earth and the existence of life is derived largely from radiometric dating.
Therefore, because Zircons always contain traces of Uranium and Thorium they are used extensively for radiometric dating.
As far as I can tell, I will still have all the benefits of the ratiometric connection, with only slight degradation in noise performance (due to the ADC performance with reduced Vref...
the closed-loop output resistance of the op-amp and its input voltage and current offsets appear to be negligible in this scenario) in terms of noise bits -- but the increased resolution more than compensates for the increase in noisy bits.
Renfrew (1973) called it 'the radiocarbon revolution' in describing its impact upon the human sciences.
Oakley (1979) suggested its development meant an almost complete re-writing of the evolution and cultural emergence of the human species.