Direct dating of tin–tungsten mineralization of the Piaotang tungsten deposit, South China, by 40Ar/39Ar progressive crushing

Dating ore minerals is the most direct method to determine the mineralization age of a deposit, but only a few ore minerals can be directly dated by traditional isotopic geochronometers. The aim of this study is to investigate the possibility of direct dating of the ore minerals cassiterite and wolframite from the Piaotang tungsten deposit using the 40Ar/39Ar stepwise crushing technique, comparing the age to coexisting K-rich muscovite dated by 40Ar/39Ar laser stepwise heating. The cassiterite, wolframite and muscovite samples were separated from four pieces of ore hand-specimens. The 40Ar/39Ar isochron ages of cassiterite and wolframite are concordant with ages of their coexisting muscovite, indicating that cassiterite and wolframite are suitable ore minerals for directly dating the ore-forming event by 40Ar/39Ar stepwise crushing.