Potassium-Argon Dating Laboratory

The Potassium-Argon Dating Laboratory is in the Department of Earth Sciences at Dartmouth College. It is equipped to use the conventional K/Ar dating technique on potassium bearing minerals. 

Lab Instructions

Download these instructions for running the Ar Apparatus (PDF).


The lab facility contains a mass spectrometer, flame photometer, mica separation table, furnaces, and clay mineral separation equipment. This K/Ar apparatus was originally built in the early 1970's and has been updated with a microcomputer controlled MS-10 mass spectrometer.

The laboratory has tackled various problems including the dating of ash from the Lucy Fossil site in Ethiopia to constrain Lucy’s age, and the dating of clay mineral diagenesis to constrain orogensis in both the Appalachians and Cordilleran Mountains Belts.