resistance is futile, you will be assimilated

[SubtleVirtue]

it refers to isotopes moving out of the mineral, not to decay of the isotopes

In geology, closure temperature (also known as blocking temperature) refers to the temperature at which a mineral or rock system becomes a closed system, meaning the diffusion of radioactive decay products or isotopes is no longer significant.

Now, be a good boy and look up ‘diffusion’.

Boru

that is what I said

decay of isotopes as a process is not included in the concept