I got this NFC-Tag and I try to do something, so that this tag can't be recognized by any nfc-tag-reader anymore. But I want to easily change this state, so that I can easily 'free' the nfc-tag so that it is working again.
What would be the best solution for this?
I thought about aluminium or other metal to place on my nfc-tag. This would work, but is there any other solution for my problem, not using any metal?
I am not an electrical engineer, so maybe my quesion is kind of stupid, I can't evaluate.
EDIT: I don't want to use metal, because if I place it on my nfc-tag, I can't see my tag anymore. Metal is very opaque. This is one of the reasons I am looking for different solutions.