Radiometric dating of minerals in metamorphic rocks usually indicates the age of the metamorphism. ... This may not always be the case because addition or loss of isotopes can occur during weathering, diagenesis and metamorphism and this will lead to errors in the calculation of the age.

Can you date metamorphic rocks?

Metamorphic rocks may also be radiometrically dated. However, radiometric dating generally yields the age of metamorphism, not the age of the original rock.

What is metamorphic dating?

When the rock again cools, the minerals close and again accumulate daughter products to record the time since the second event. ... Remarkably, the isotopes remain within the rock sample analyzed, and so a suite of whole rocks can still provide a valid primary age.