Sample quality index to preselect suitable carbonate samples for alpha spectrometry U/Th dating

► Twenty thermogene travertine samples have been dated by means of the U/Th method. ► A mineralogical, petrographic and chemical characterisation was previously performed. ► A screening method is proposed based on a statistical analysis. ► 4 variables have been used to preselect the most suitable samples to be dated. ► A numerical index has been developed to quantitatively show the suitability of samples.