Pork Grease and 0-1

[blgoode]

This had a nice patina on my 0-1 blade but I think orange juice took it off? Is this possible? The pork grease had a nice rainbowish purple. Maybe this was just surface patina and not deep steel discoloration? Oh hell...what am I talking about

 

[mete]

Patina is only a surface thing ,oxides and such. The citric acid in orange juice can remove it.