Fixing and preserving the patina on a coin or object

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Roberts
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Fixing and preserving the patina on a coin or object

Post by Roberts » Sat Feb 10, 2018 1:24 pm

This should only be used on coins/objects that you keep for your personal pleasure as its halts the detoriation process and preserves "frail" patina from drying and crumbling.

2 centimes napoleon.png

Thought i would post up a few tried and tested cleaning methods that might help others(aimed at a coin or object that has been cleaned and has a patina)

Once an object has been taken from the ground and cleaned it will naturally start drying out if the object has a patina then this also will dry out and start to crack and fall off. The most imortant thing after cleaning to do for patina is too immediatly apply a fixater or a product that will stop the detoriation and preserve the object.

Preserving the Patina after cleaning Natural bee's wax

Natural Bee's wax comes in hardened form and usually needs to be mixed with terabathine essence to become a cream before applying to objects. The easiest thing to do and works just as well is to buy "antique furniture polish" with a high degree of natural bee's wax content, which can be brought from most D.I.Y stores.

Apply a thin layer to object leave to dry and polish with a soft cloth in circular motions, the result will be a clean shiny object with a preserved patina. Note: You can apply another layer once first is dry to be sure.

** For the Experts You can buy a block of bees wax in natural form and melt it down and add terabathine essence.

** Another method (cold) is you can just break down the bees wax and place into a pot and fill with terabathine essence until the wax is covered, shake and let the wax dissolve for 2/3hours. After the 2 hour wait spoon mix vigourously to obtain a (smooth) creme ready to apply. NOTE if the cream is too thick add a little more terabathine and more wax if to thin.

Parafine Reversible, Used more on dark patined objects.

Buy parafine granules used for making jams etc.

Melt the parafine either in a pot or "bain marie"

Once the parafine has dissolved & at boiling point dunk the object into the liquid until it changes to a darker color (all oxygen has been expulsed) then take out and pat dry to take off the excess parafine and leave just a fine layer, leave to dry. (do not apply any other products).

Petroleum jelly(vasaline) and zinc oxide 15% (mixed)for grey or blackish patina Reversible.

This creme is usually used on the darker patina and will also create a dark Patina if applied to an object. Same as above methods apply a thin later and when dry polish in circular motions. If you do use this method then do not apply bees wax or other products afterwards.

Fixing a patina
(irreversible)To be used with caution.

Again once the object is clean and the patina needs to be preserved, there is the option of fixing the patina using a product "Paraloid b72" (Irreversible) that will coat the object in a thin transparent resin. This is irriversable but does preserve the object for eternity.(you can always add the bees wax method to make the object shine and bring out the details)

Paraloid b72 (Irreversible) is a product which is used in the preservation of objects and can easily be made at home which i will not explain here but you can buy this product already mixed and it can be used immediatly on objects. (can be obtained on the internet or specialist stores).

I hope that some of these methods can help other members and are just a few things that i have picked up over the years and thought i would share.

Regards, roberts
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Last edited by Roberts on Thu Feb 22, 2018 1:51 pm, edited 20 times in total.


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Re: fixing and preserving the patina on a coin or object

Post by Me and my boy » Sat Feb 10, 2018 1:33 pm

I would just add that I wouldn’t clean or wax anything of value as the flo and museums arnt too keen. It’s ok if it’s an old Roman grot etc but make sure your possibly not devaluing a rare or expensive item.
Museums used to use a preserving wax but I think they keep things as is now! Not 100% sure though on their current process.
Just air on the side of caution
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Re: fixing and preserving the patina on a coin or object

Post by Twit » Sat Feb 10, 2018 3:05 pm

Me and my boy wrote:
Sat Feb 10, 2018 1:33 pm
I would just add that I wouldn’t clean or wax anything of value as the flo and museums arnt too keen. It’s ok if it’s an old Roman grot etc but make sure your possibly not devaluing a rare or expensive item.
Museums used to use a preserving wax but I think they keep things as is now! Not 100% sure though on their current process.
Just air on the side of caution
I agree there on caution... it is a topic that has its arguments, as with cleaning, and no set reply.

Almost all coins will not deteriorate further if stored properly and handled carefully . Adding sealant can make some patinas stronger, protect them from handling, and to a certain extent the environment. They can also make it hard to further preserve the coins, sometimes even damage the coins. For some less valuable coins being kept for show and handling it might make sense, but for others that are rarer I would think twice and make sure that any sealant was both removable and certain not to damage the item.

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