Dirty calcites 1. Uranium-series dating of contaminated calcite using leachates alone

Chemically precipitated calcite (travertine, speleothem, calcrete) generally contains admixed detritus which will contribute some Th and U during dissolution in dilute acid. This will introduce errors during230Th-23U dating of the calcite, unless corrections are made for the detrital components of230Th and234U. Isotopic data from analyses of leachates (L) of several coeval sub-samples of such rock can be used to obtain the age of the chemically …