Necron Artefacts

Hi,

Maybe this should be in the Necron forum but I was wondering how the artefacts of the aeons and the artefacts from the mephrit dynasty interact. I've been told you can take them from both but this seems contrary to convention? In the army list it says characters from mephrit detachment can take from the below list, but nothing about mixing or even being allowed to take from the parent codex. Any thoughts?