[aslyfox]

This is what I do, too.
After formatting an SD card I photograph such a card first.

Didn't help to get my stolen K5 back, though.

don't know if this would have helped in your situation but I have registered my gear with Lenstag in an attempt to help with recovery should I suffer theft of any of it:

Lenstag - Protect your camera equipment, images and help make the world safer for photography on iOS, Android and the web.

what is Lenstag -

" Lenstag is a recently-launched, free online service for iOS, Android, and the web that records the serial numbers of your lenses, cameras, flashes, laptops and anything else in a secure, private registry before they are stolen.

If one or more of your items disappear, you can immediately flag the missing items as stolen which creates a public web page, quickly indexed by search engines. The serial number is then discoverable by a single Google search (example: ‘75165 lenstag’) or by checking the Lenstag apps. Thanks to Lenstag’s growing relationships with the pawn shop industry and law enforcement, the exchange of money for that stolen item becomes much more difficult akin to trying to sell a stolen vehicle. The idea behind this service is that if everyone gets into the habit of checking serials numbers online before purchasing used equipment, it will become harder and harder over time to peddle hot items and thieves will get arrested when they try to pawn them. Think of it like a DMV for camera equipment. The more people who register their gear, the more effective the registry system becomes. . . . "

https://digital-photography-school.com/lenstag-camera-theft/