Solve it Sunday: Gold Standard

This question may seem laughable at first glance. I assure you, however, that I have no intention of making sport with you. Simplicity does not always indicate triviality.

Which is heavier – a 1-ton block of wood, or a 1-ton block of gold?

You may assume that both blocks are being weighed on the same weighing apparatus in the same terrestrial location, and that the machine is giving an identical value in both cases.

Good luck with this one! It’s not as simple as you might think it is.
As always, answers in the comments.