“…Thorium concentrations (Table ) of the analyzed monazite crystals are similar to other dated Alpine cleft monazites [ Gasquet et al ., ; Janots et al ., ; Berger et al ., ; Gnos et al ., ]. Uranium concentrations are very low, as seems to be characteristic for hydrothermal cleft monazite [e.g., Catlos , ; Janots et al ., ], with the lowest values reported for highly oxidizing conditions [ Gnos et al ., ]. The high Th/U ratios of 360–995 of monazite PK2 (horizontal cleft), along with hematite and senaite in the cleft, therefore reflect the highly oxidizing conditions in this cleft.…”