I would like to quote table 4.4: Radiometric ages of some early Archean and Related Rocks of the Pilbara block, Western Australia
Pilbara Supergroup Method
Marble Bar U-Pb 3.45+/- 0.02 Ga
Marble Bar Rb-Sr 3.23+/-0.28 Ga
Warrery Gap Rb-Sr 3.51+/- 0.06 Ga
North Star Basalt
Marble Bar Rb-Sr 3.57+/- 0.18 Ga
Marble Bar Sm-Nd 3.56+/- 0.54 Ga
Marble Bar Sm-Nd 3.56+/- 0.03 Ga
Method:
U-Pb: Discordia-Concordia technique using Uranium/Lead
Rb-Sr: Rubidium/Strotium isochron method
Sm-Nd: Another Isochron method
Notice how various methods all come up with virtually the same age.