So I found a pair of cheap garden shears that had been left outside in the rain for, oh, a year or so.  Decided to play with them a bit.  First I pulled/broke off the plastic handles, and then decided to de-rust it.  Lowe's didn't have Evapo-Rust, so I picked up a bottle of rust remover - aka phosphoric acid.  Instructions were for rust removal (full strength) and paint prep (25% solution with water.) Decided to go with the latter.  Soaked for a day and could then get the nut loose, disassembled, soaked for another day, then forgot about it for another couple.

Today I pull the parts out and they are nice and clean.  Wash off with water, and in a couple of seconds I start to see flash rust.  Boild some water and pour it over the parts - that heats them up so that they dry more quickly.  No joy.  So I figure I'll really heat them up.  Boiled them in a SS pot for about half an hour, mainly to convert the flash rust to "blue" - I was doing to plasti-dip the handles anyway.

So I pull them out, and damned if they don't look parkerized, or at least phosphatized.

Do I need to throw away that pot?  Will my shears explode if I use them? (I'll try to get pics up, probably tomorrow when the Plasti-dip dries.

The main thing is, did you discover that the price of a brand-new pair of garden shears is cheaper than a bottle of Evapo-Rust and a new pan?  

I needed the rust remover anyway - this was sort of a test run.  And I'm actually pretty particular about garden shears - if I'm buying them it's Felco.  But these were some random POS's I'll use for trimming my forlorn bonsai at work.

As for the pan?  Eh, how poisonous could it be?

Pot will not explode......though I once blew up a pyrex pan being stupid.  thank GOD my back was turned.

Sheers are likely, essentially, rust blued.  You could card them, let them lightly rust, boil them, card, rust boil,card, etc and end up with some pretty sheers!!!!

Interesting.  Though the surface wasn't black, more gray with a greenish brown tinge - I'll try to post a pic.  I actually wound up using a wire wheel to remove most of whatever coating was on there.  I went to Plastidip the handles and some of the surfaces needed smoothing; by the time I was done with the grinding wheel, I figured what the hell and kept going with the wire wheel.