Zircon
Zircon
Zircon has played an important role during the evolution ofĀ radiometric dating. Zircons contain trace amounts of uranium and thorium (from 10Ā ppmĀ up to 1 wt%) and can be dated using several modern analytical techniques. Because zircons can survive geologic processes likeĀ erosion, transport, even high-gradeĀ metamorphism, they contain a rich and varied record of geological processes.
Zircons fromĀ Jack HillsĀ in theĀ Narryer Gneiss Terrane,Ā Yilgarn Craton,Ā Western Australia, have yieldedĀ U-PbĀ ages up to 4.404 billion years,Ā interpreted to be the age of crystallization, making them theĀ oldest mineralsĀ so far dated on Earth.
