Seen a video lately where an old video game console, knife, tool or other seemingly ruined item is "restored"? You likely suspect fakery now and again, but you likely don't know how systematic the fakery has gotten—like the Primitive Technology clones, it's a lucrative genre. Backyard Ballistics, specializing in guns, says that most such videos are fake—and offers some tips on how to spot them.
For example, steel is not copper!
"If you're looking at a steel object with green stuff on it, what you're looking at is most certainly fake." Another good one: when 'rust' is marked by unrusted shadows beneath rings and other protuberances. That's a good sign that it, or the cause of it, was sprayed on. The author cautions that in the latter case (i.e. accelerated corrosion) there may still be some use to the video—and also warns that some of the common "tells" about fakery are nothing of the sort.