What have done towards your prep?

[NorthernRaider]

I bought a value tin opener from tesco a few months ago and put it away in a box, I was sorting out those boxes the other day and the tin opener was rusty and had green stuff growing on it... I hadn't used it and it was the only thing that seemed affected. It would've been something I'd have put away and not checked on or rotated, but I'm glad I did and now know to keep an eye on everything.

Hmmm sounds like some part of the tin opener had a few copper componants under the nickel coating and verde de gris has formed as the copper oxidises, I cannot see this being mould unless you put it away dirty. Sounds very much like its made of such cheap materials like a copper and mild steel componants coated in zinc plating to make it look nice. Maybe better looking for a stainless steel one.