Yesterday's Keepers. Need some Advise

[ArDirtSlinger]

Went out for a couple of hours yesterday and pulled these tidbits.


The mainspring is soaking in a Phosphoric acid solution and should clean up nicely.
The brass pieces I believe to be part of some sort of unit badge. Possibly similar to a Hardy hat emblem.
How do I go about cleaning it without losing any detail that is left. It has sunburst edges and a curved ribbon in the middle. Possibly letters on it. It is fairly thin so I need to be gentle. Also it looks to be stamped.

 

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[trapperart]

Congrats on your finds

 

[Geochem]

Nice find!

For brass, it is difficult to remove a heavy tarnish crust and not at the same time also remove a small layer of brass underneath.

To remove highly corroded metal but limit inducing corrosion on the more solid brass surface underneath it is often best achieved by use of a very weak carboxylic acid, used at low solution concentration, and with short dissolution soak times.

In your kitchen you may already have a very weak organic acid, as in Cream of Tartar, which is tartaric acid, a mild dicarboxylic acid (two carboxyl acid groups per one molecule). Make a low concentration solution, like 2% to 5% tartaric and add a few drops of disk soap.

Citric acid is a tricarboxylic acid that has more reactivity (more acidic strength) then very weak carboxylic acids like tartaric, succinic, glutaric, and the like.

Once low solution concentration of weak dicarboxylic acids become spent the carboxylate groups that remain then act as a chelant. The dicarboxylate groups have the chemical property to grab onto/chelate the metals on the metal surface and as a film act to prevent further acidic corrosion. Just work slow at room temperature and brass surface corrosion will be minimized. Soak in an alkaline solution like 0.1% regular dish soap solution to remove any residual acids on the metal. Then rinse well with tap water, let completely dry, and then soak for several hours in mineral oil to oil wet the metal surface (which will keep the atmospheric oxygen from further corroding the cleaned up surface) and wipe away excess oil.

 

[against the wind]

Congratulations on your finds,,
Best of luck with the cleaning.

 

[ArDirtSlinger]

Geochem.
Thanks for the input. I used lemon juice and q-tips. I can see now that is in fact the center top part of a Hardee pin. I'll be going back tomorrow to see if I can find some more of it. I was looking at it upside down lol

 

[vpnavy]

Nice finds ArDirtSlinger!

 

[fmrUSMC_0844]

Nice finds!! The brass piece looks to be the remains of a Jefferson Davis Hat Pin. Its also called a Hardee hat Pin I believe. Heres one I found in 2013.