How cheap are laser engraving machines? For ultra critical keys and generationally important data this sounds like a really good idea. I use M-disc currently but an engraved A4 or Letter size scannable durable material seems like the best option if it is available.
Since it seems to accept an image, the question is what material would be best to run it on and then have it be scannable well on a standard flat bed scanner, which almost certainly will be available in some form as long as our current civilization survives.
Edit: would this work?
https://a.co/d/5fWJaEa
Since it seems to accept an image, the question is what material would be best to run it on and then have it be scannable well on a standard flat bed scanner, which almost certainly will be available in some form as long as our current civilization survives.