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World's smallest QR code, smaller than bacteria, could store data for centuries
(www.sciencedaily.com)
This is a most excellent place for technology news and articles.
As the article explains, the whole purpose here is to be able to store data on a medium that can endure harsh conditions, including heat, moisture, radiation, and physical abrasion. The company's website claims the medium can retain data for 5000 years without power, and is water and fire resistant.
The underlying ceramic film is already used for protecting tools like drill bits and saw blades from physical damage, which is why it was chosen for this project. They already found one of the most durable materials in the world, and asked whether they could store data using that already-durable material.
The fact that the material is resistant itself does not mean that a layer of atoms of a few nanometers of thickness is scratch resistant itself. I guess you'd have to store it in a protected area and handle it with gloves, which doesn't feel much more appealing than magnetic tape.
In a drill bit you don't really care if a few atoms on the external surface fly off, in this case you would.