Giving copper/brass "patina" ideas pls

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mrspatch
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As per subject.. What do people use please?

Even a toasted old copper.. It's nice to know who the monarch was.. But after it has been cleaned within an inch of its life to reveal a bust.. Is there a good way to darken it a little bit please?

Thank you.

Louise 😊
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Littleboot
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In my experience the less you 'do' with old copper/bronze etc the better. You may produce what you feel is a patina and have a coin or object which looks OK. For a while.
I avoid using water and don't use solvents. In fact if I have what I feel may be a valuable copper (we get a lot of hammered copper alloy coins in France) I tend to thoroughly dry it then apply some Renaissance Wax and 'push' the dirt off gently. You are never going to replicate a patina which has built over hundreds of years so better to keep it in tact.
Any copper alloy 'cleaned within an inch of it's life' will have zero value. So I suppose if it is something you clean in order to establish exactly what, and who, it is (we all do that) then -assuming it is dry and free of bronze disease- a light coat of the previously mentioned wax and a gentle buff would be my option.
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mrspatch
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Littleboot wrote: ↑Wed Jun 19, 2024 10:09 am In my experience the less you 'do' with old copper/bronze etc the better. You may produce what you feel is a patina and have a coin or object which looks OK. For a while.
I avoid using water and don't use solvents. In fact if I have what I feel may be a valuable copper (we get a lot of hammered copper alloy coins in France) I tend to thoroughly dry it then apply some Renaissance Wax and 'push' the dirt off gently. You are never going to replicate a patina which has built over hundreds of years so better to keep it in tact.
Any copper alloy 'cleaned within an inch of it's life' will have zero value. So I suppose if it is something you clean in order to establish exactly what, and who, it is (we all do that) then -assuming it is dry and free of bronze disease- a light coat of the previously mentioned wax and a gentle buff would be my option.
Most of our coppers are Georgian and completely worthless but also in really bad condition.. Sometimes it's nice to just dull the shine back down. Are your copper hammereds Jettons? Love Jettons 😍
slippery
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Antique restorers use a patination fluid for aging copper and brass to say get a new brass handle to match an existing set, I've never used it on coins but no reason it wouldn't work (only needs to be in contact with the liquid for a very short time usually,if it goes too dark then you'll need to gently rub the surface till it gets somewhere back to where you like the colour)Try googling Antiquing Fluid or cold patination liquid.
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mrspatch
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Ooh.. I'll have a look.. Thank you 😊
Pete E
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There is a product called "Liver of Sulfur" which is advertised as suitable for restoring the patina on silver bronze and copper...

It's sold on eBay, and you only need a small amount...for use on silver coins they talk about adding just a couple drops to a glass of water...

I know the product works well on silver, but I am a bit sceptical about bronze and copper, but who knows....it's also relatively cheap so no great loss if it doesn't work as claimed....
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Easylife
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Plenty of methods on Google to achieve certain colours of patina. :thumbsup:
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HammeredDeus
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mrspatch wrote: ↑Tue Jun 18, 2024 6:54 pm As per subject.. What do people use please?

Even a toasted old copper.. It's nice to know who the monarch was.. But after it has been cleaned within an inch of its life to reveal a bust.. Is there a good way to darken it a little bit please?

Thank you.

Louise 😊
On the old Georgian/Victorian coppers that I've experimented with, much of the detail is actually in the corrosion products, and removing them ends up removing detail. Judicious use of mechanical rather than chemical methods e.g. a small piece of thin carbon fibre rod from a broken kite sharpened to a point (or a cleaning pencil from the usual suppliers) has given the best results on the crustiest coins - although it's dusty and time consuming!
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Littleboot
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mrspatch wrote: ↑Wed Jun 19, 2024 10:14 am Most of our coppers are Georgian and completely worthless but also in really bad condition.. Sometimes it's nice to just dull the shine back down. Are your copper hammereds Jettons? Love Jettons 😍
No, not jettons. (Though. of course, we get those too.) These are small change 1, 2, and 3 Deniers coins. (Tournois and Liards). In the 16th century someone decided that the smaller currency should be made of copper alloy instead of base silver. I hope that person in being toasted in the deepest level of Hell. :lol: Because I have found thousands upon thousands of these things. Usually they are completely bald. Anyone who detects mainly in France for any length of time, will tell you the same. The coins are similar in size to a rose farthing of the same era.

Georgian coins are notorious for not lasting in the ground. Quality of metal I suppose. We have the same issue over here in France with the very similar sized Louis 15 and early Louis 16 coins of the exact same time period. Most of them have just a crusted residue which follows the design. If you do anything too vigorous it simply flakes off, as HammeredD says. I remember digging some decent Georgian coins back in the 70's and early 80's. The chemicals now dousing the land are, IMO, responsible for the difference in quality of the coins dug these days.
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mrspatch
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HammeredDeus wrote: ↑Thu Jun 20, 2024 8:43 am On the old Georgian/Victorian coppers that I've experimented with, much of the detail is actually in the corrosion products, and removing them ends up removing detail. Judicious use of mechanical rather than chemical methods e.g. a small piece of thin carbon fibre rod from a broken kite sharpened to a point (or a cleaning pencil from the usual suppliers) has given the best results on the crustiest coins - although it's dusty and time consuming!
That's why I let hubby mechanically clean hahaha.. πŸ˜‚πŸ˜‚
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