Conserving Detected Dug Coins & Relics

[JCR]

I have found Copper based artifacts to be the trickiest to clean. A LONG soak in distilled water with careful toothpicking is my standard. Hydrogen peroxide for any final finish work is safe for Copper. You can let it soak until it stops bubbling & do it again if needed. Navel/Aluminum jelly is harsh on Copper or Nickel but works well if used carefully on gilt, and works great on Aluminum. There really are no set best procedures, each piece is different & environmental damage will still be there. I'm still experimenting.

[Zincoln]

Good day Brian,

I'm w/ the Tom's on this one.  I use peroxide on all my copper/brass that is looking crusty, and gently swab them with a Qtip while still wet.  The only downside i see is that they often turn a nearly black color for me as the verdigris absorbs the chemical reaction, but some retain the green or gain is back over time - seems random.  Tends to even out discolorations as they tone also.  I've never tried leaving it in the microwave, just boiling the peroxide first and then submerging on the counter...but will have to give it a shot.   Seems to harden the edge verdigris that often flakes away. Figure you can't hurt a coin that is already damaged.

For relics and nickels, i like Acidmagic that you get at any big box HW store.   Really cleans up those items if you are simply looking to display and they don't have any unique value.  Quick bath, brass brush, fresh water.

Pictures of an 08s IHC that needed some help and got the peroxide (i know, rare, but not going to hurt it when covered in concreted dirt and suffering splotchy verdigris - least now it can be conserved and enjoyed), and some 1800s GT relics before/after w/ the acid.

Been a long time since we met in NV if I recall correctly!

HH,
Zincoln (Brian)

[JCR]

@Zincoln  What is the Acidmagic marketed for in the hardware stores? I have not seen that brand name locally.

[PimentoUK]

I believe it's "Certol International Acid Magic" , aimed at swimming pool cleaning:
https://www.certol.com/landingpages/acidmagichome/

The safety data sheets give little insight into it's chemical composition, other than hydrochloric acid plus 'trade  secret mystery ingredients', which are certainly what chemists call 'buffers'.

Despite their 'International' name, their products seem limited to US and Canada. So no chance of finding it here in the U.K.

( domestic pools are not common, here, either, so finding an equivalent could be tricky)

[GB_Amateur]

36 minutes ago, PimentoUK said:

I believe it's "Certol International Acid Magic"

At Amazon:  https://www.amazon.com/CERTOL-INTERNATIONAL-USA-128-1-Replacement/dp/B000KKQ8LA/ref=sr_1_4?keywords=acid+magic&qid=1640812364&sr=8-4

[F350Platinum]

You should be able to get muriatic acid at a drugstore as well. 🙂

[Zincoln]

You guys nailed it with the above description.  I use it for cleaning masonry.  Muriatic (or hydrochloric) acid.  They don't give you the dilutions or any extra added components on the labels.  Believe I've been using it undiluted for cleaning.

Zincoln

[PimentoUK]

For you US folks, there's another alternative to Acid Magic:
"Acid Blue" by Champion:

https://www.leisurepoolinc.com/shop/pool-spa-chemicals/balancers/ph-balancers/acid-blue-buffered-low-fume-muriatic-acid-1-gallon/

 

 

[Doc Bach]

On 12/29/2021 at 7:08 AM, JCR said:

I have found Copper based artifacts to be the trickiest to clean. A LONG soak in distilled water with careful toothpicking is my standard. Hydrogen peroxide for any final finish work is safe for Copper. You can let it soak until it stops bubbling & do it again if needed. Navel/Aluminum jelly is harsh on Copper or Nickel but works well if used carefully on gilt, and works great on Aluminum. There really are no set best procedures, each piece is different & environmental damage will still be there. I'm still experimenting.

Howdy JCR I have been wanting to try a new and diffirent approach to cleaning up some recently dug flower and military buttons that still retain considerable gilt.Did you settle on and can you recommend any particular brand of Navel/Aluminum jelly? Any advice would be appreciated thanks, DB.

[JCR]

The brand my local Ace Hardware carries is Loctite.  

On gilt, I would try lemon juice first after gently cleaning off any dirt. The Navel Jelly as a last resort on stubborn ones.