Help me. What does "gilt" mean in numismatic terms? At first, I thought is was left over Hanukkah candy, but that's "gelt". Then it's not a former male horse, either. Did the coin do something wrong (no, that's guilt)?
<< <i>Help me. What does "gilt" mean in numismatic terms? At first, I thought is was left over Hanukkah candy, but that's "gelt". Then it's not a former male horse, either. Did the coin do something wrong (no, that's guilt)? >>
"Gilt" or "gilding" is a the application of a very thin layer of precious meta, in this case gold, that gives this pattern coin the appearance of what it would look like if it were sold gold.
Retired dealer and avid collector of U.S. type coins, 19th century presidential campaign medalets and selected medals. In recent years I have been working on a set of British coins - at least one coin from each king or queen who issued pieces that are collectible. I am also collecting at least one coin for each Roman emperor from Julius Caesar to ... ?
Obviously I'm out of my league here, and I was trying to be humorous before, but with the answer Bill gave me, it would seem that the original coin was not gold, but was "gilt" after minting. Could it be gold and needed an extra layer after minting to look good? Was this pattern coin made out of some other metal that someone "gilt" to make it look like gold?
<< <i>Obviously I'm out of my league here, and I was trying to be humorous before, but with the answer Bill gave me, it would seem that the original coin was not gold, but was "gilt" after minting. Could it be gold and needed an extra layer after minting to look good? Was this pattern coin made out of some other metal that someone "gilt" to make it look like gold? >>
It was very common for the mint to strike patterns for gold coinage in materials that cost much much less than gold and then simply gilt it. This coin is copper.
Ed62 - I've wondered the same about this coin - looking forward to seeing some answers, if offered.
"My friends who see my collection sometimes ask what something costs. I tell them and they are in awe at my stupidity." (Baccaruda, 12/03).I find it hard to believe that he (Trump) rushed to some hotel to meet girls of loose morals, although ours are undoubtedly the best in the world. (Putin 1/17) Gone but not forgotten. IGWT, Speedy, Bear, BigE, HokieFore, John Burns, Russ, TahoeDale, Dahlonega, Astrorat, Stewart Blay, Oldhoopster, Broadstruck, Ricko.
Ed62 - I'm not as inquisitive as you are - I always assumed it was afterwards........but maybe not.
"My friends who see my collection sometimes ask what something costs. I tell them and they are in awe at my stupidity." (Baccaruda, 12/03).I find it hard to believe that he (Trump) rushed to some hotel to meet girls of loose morals, although ours are undoubtedly the best in the world. (Putin 1/17) Gone but not forgotten. IGWT, Speedy, Bear, BigE, HokieFore, John Burns, Russ, TahoeDale, Dahlonega, Astrorat, Stewart Blay, Oldhoopster, Broadstruck, Ricko.
The question of before vs after strike gilting comes up on a gilt cameo coin like the one below. If the coin is gilt after striking it seems the cameo effect would not stand out as the frosted devices would be covered by the same layer of gold as as the mirror-like fields and greatly diminish the cameo effect. I realize the layer of gold plating is very thin, but . . . . . . .
Someone more familiar with minting and striking may know but I would think that the pressure required to strike up a coin would totally obliterate the uber-thin layer of gilt.
Copper is not the only material that has been gilt. There are aluminum gilt ones too. Which is odd because back then aluminum was just about as spendy as gold.
<< <i>Someone more familiar with minting and striking may know but I would think that the pressure required to strike up a coin would totally obliterate the uber-thin layer of gilt. >>
Agreed, but at the same time, how would gilting a coin after striking it result in a cameo effect? I can see the entire surface having mirrors by the gilt but it seems unlikely that the devices will have mint "frost" on them.
<< <i>They sure as heck weren't minted, and the gilt application takes on all of the underlying detail. >>
Interesting, yes I have seen plated jewelry where the gold plating forms all the pockmarks of the metal underneath, but is it possible for the gold to take on all the miniscule flow lines that give the coin P/L surfaces and the frosty devices? I wouldn't doubt the gold would take on nuances of the underlying surfaces, but I would still think it would exhibit the flashy reflectiveness of plated gold throughout the entire coin irregardless of how the metal is underneath.
That Irish penny was struck at the Soho Mint in Britain, which had the cutting-edge technology of the time. I think they were the first to use steam presses? It was in an NGC PF64 UCAM holder, as I recall. I sure do miss it. It definitely had UCAM/DCAM contrast.
I don't see how it's possible to gilt the coin/planchet before striking and still get a satisfactory coin. Since the gilt is microscopically thin, the metal deformation and movement during striking would tear the gilt layer resulting in the base metal showing through on the surface of the coin.
Worry is the interest you pay on a debt you may not owe.
This is mine. I have zero photo skills but I can scan with the best of them. If there are any parts anyone would like to see at higher resolution that might help prove one way or another how these things come to be, I can do that.
<< <i>This is mine. I have zero photo skills but I can scan with the best of them. If there are any parts anyone would like to see at higher resolution that might help prove one way or another how these things come to be, I can do that. >>
Hi,
Is the coin CAM/DCAM? If so, how do the devices look in hand? Are they frosty like a proof gold coin or flashy throughout? Thanks.
<< <i>I don't see how it's possible to gilt the coin/planchet before striking and still get a satisfactory coin. Since the gilt is microscopically thin, the metal deformation and movement during striking would tear the gilt layer resulting in the base metal showing through on the surface of the coin. >>
I concur. The stamping process requires melting the top layer of metal to get it to flow into voids in the die.
Smooth transactions with Gerard, mkman123, joebb21
<< <i>I don't see how it's possible to gilt the coin/planchet before striking and still get a satisfactory coin. Since the gilt is microscopically thin, the metal deformation and movement during striking would tear the gilt layer resulting in the base metal showing through on the surface of the coin. >>
I concur. The stamping process requires melting the top layer of metal to get it to flow into voids in the die. >>
I don't believe they melt it, they merely heat up the planchet and then wash it before upsetting the rims and then it goes straight to striking. The melting points of gold and copper are pretty close.
Seriously? If so, I'd start by asking Kagin. Your piece is ex Robert Bass and it's plated in that catalog.
Yep - I bought 6 coins or so from that collection when it was broken up.
"My friends who see my collection sometimes ask what something costs. I tell them and they are in awe at my stupidity." (Baccaruda, 12/03).I find it hard to believe that he (Trump) rushed to some hotel to meet girls of loose morals, although ours are undoubtedly the best in the world. (Putin 1/17) Gone but not forgotten. IGWT, Speedy, Bear, BigE, HokieFore, John Burns, Russ, TahoeDale, Dahlonega, Astrorat, Stewart Blay, Oldhoopster, Broadstruck, Ricko.
though I'm uncertain exactly how the Gilding is done my thinking is that it isn't with a thin film. this process is a "lost art form" that the Mint employed in the 19th century along with Bronzing of medals, where a powdered Bronze is mixed with linseed oil or something similar, applied to the medal and baked. all the Bronzed medals I have or have seen are on a Copper planchet(Bronzed Copper) and all the Gilt medals I'm familiar with are Bronze planchets with Gold Gilt(these are often easy to distinguish when the Gilding wears in some places to expose the underlying metal). I suspect that the process used is similar to plating without the use of an electric current or similar reaction; the Gold is somehow dissolved and applied to the surface in a non-destructive manner.
Several years ago I bought a pair of US Mint dies used to strike the Panama-California So-Called Dollars, along with several struck pieces and a blank planchet. Normally you can'treally authenticate a blank planchet like that, but I'm pretty confident about what it is, considering the pieces that came with it. (original thread).
The planchet was unquestionably gilt.
So, I'm pretty certainly that at least some pieces were gilt before being struck.
Many of the gilt coins were plated after striking. It was very common years ago. To be quite honest, I am unable to tell, other than the Irish coin certainly looks like it was struck on a gilt planchet.
It is very intuitive, IMHO.
PNG member, numismatic dealer since 1965. Operates a retail store, also has exhibited at over 1000 shows. I firmly believe in numismatics as the world's greatest hobby, but recognize that this is a luxury and without collectors, we can all spend/melt our collections/inventories.
<< <i>what is your thinking on how the gilding is done?? >>
I'm thinking that we really need a metallurgist to weigh in here.
I'm thinking that it would also be a great opportunity for our hosts to share some of their experience, if they choose to. I know that I've seen plenty of pieces from across the street, both slabbed and unslabbed, where I could only wonder how they came to their conclusions .The grading services are making tis decision, somehow.
Beyond that... we've had plated Lincoln cents for almost 30 years and after they worked out the kinks in the first year or two I can't think of the last time I saw torn plating on a normally struck coin (errors don't count here). It's clearly possible to strike plated planchets with good quality in the finished product, even if I don't know how it's done.
So, I'm pretty certainly that at least some pieces were gilt before being struck. >>
Because you own a gilt planchet (which is way cool BTW) does not necessarily mean that the planchets were gilded and then struck. The fact that that exists could simply have been the result of a process to test the reaction of the base metal with the gilt to see how it would hold up. And yes it very well could have been struck, but the existence of a gilt planchet does not automatically mean that it was subsequently struck.
<< <i>I don't see how it's possible to gilt the coin/planchet before striking and still get a satisfactory coin. Since the gilt is microscopically thin, the metal deformation and movement during striking would tear the gilt layer resulting in the base metal showing through on the surface of the coin. >>
I concur. The stamping process requires melting the top layer of metal to get it to flow into voids in the die. >>
I've personally minted both types: A) Gold-plated prior to striking. Gold-plated after striking.
Both will work, and it is not generally possible to distinguish one from the other.
The layer of gold (typically from electro-plating) is very thin. But this layer will stretch considerably. The gilt layer does NOT "tear" or leave gaps or voids upon striking. And the top surface of the struck coin does NOT melt. In fact, normally-struck coins that I drop into my hand the instant after they are struck do not even feel warm.
Whatever surface texture a coin has will usually be preserved after electro-plating. The only exception is a toned coin (the electro-plating acids will react with the oxidized metal). So if a coin has an un-toned proof finish, it will still have that same finish after electro-plating.
Here is a coin that was gold-plated prior to over-striking:
I do not have a picture handy of a coin that I plated after striking, but I will try and take one and post it here.
Some of the gold denomination U.S. pattern issues have even been glided after they were issued by the mint by early collectors who either wanted them to look like gold or just to protect them.
This SC$1 is a HK unlisted variety for having been struck on a gilt planchet. It was definitely struck on a gilt planchet instead of gilded afterward. With a 10x loupe you can actually see white ghosting within the patina on the lower reverse "Commenced & Finished" from each repeated strike. You can see a ghost “C” to the left of the “C” in Commenced and another “C” below the main “C”. This ripple or shock wave effect from each repeated die strike continues down to the rim with both words and dates "Commenced & Finished". Due to William Key's high relief design I can actually count that it’s been struck a minimum of 4 times. Sorry I'm not able to show more details as proof type issues are tough for me to photograph. When directly angled into a light source they entire fields on this medal become fully deep proof like, the patina vanishes, and the ghosting can be more easily seen.
To Err Is Human.... To Collect Err's Is Just Too Much Darn Tootin Fun!
Well I really can't say about US coins, but it seems to me that the early British gilt and bronzed coppers were done prior to striking. This is generally inferred rather than absolutely proven although several researchers seem to belive it well proven. Peck for example discusses ( note 1 page 400) some "exceptionally well gilded after striking" examples. And futher states that the mint asserted during the period that no gilt specimens were issued.
Earlier in his tome he discusses restrikes by Taylor which used prepatinated blanks, and on page 226 states that " the process of striking on pre-gilded and pre-patinated bronze blanks was Boultons invention". Much research has taken place on the earlier (1672-1775) gilt and bronzed British coins and the majority opinion is that these are all later additions to currency coins. For example there are many early farthing pieces from Charles 1 through Anne that are silver plated, and whether done by the mint or not it seems to me that these were all done post striking.
Personally I am convinced that the genuine early pieces (beginning with Soho mint) were gilt or bronzed prior to striking, although there are quite a few (fakes/restrikes/call them what you will) that were done post striking.
so it seems clear that Gilding was done both before as well as after striking coins/medals, but what of the process itself?? can anyone enlighten the forum about how it's done.
Here is a coin that had selective gold-plating after striking. A close-up of the "S" mint mark area, where some of the gold plating covered the original coin's surface, you can see that the original mint luster is intact and undisturbed by the thin coating of gold.
Awesome images dcarr. Have you tried plating some of your proof coins? I'm really curious as to how a proof plated post-strike will come out looking. Thanks.
<< <i>so it seems clear that Gilding was done both before as well as after striking coins/medals, but what of the process itself?? can anyone enlighten the forum about how it's done.
.......................nice medal, Frank!! >>
Gold plating solution has two formulas: cyanide based and acid-based. With either type, the item to be plated is connected to a negative terminal (cathode). This is the terminal that attracts positively charged (+) ions. The item is submerged in the solution containing dissolved gold. The positive terminal (anode) is placed into the solution, but not touching the object. A voltage is applied across the terminals (typically 2 to 12 volts DC). Positively-charged gold ions are attracted to the cathode (which is essentially the item being plated). When the gold ions contact the object, they "grab" an electron and bond to the object and form a coating of gold.
<< <i>Awesome images Dan. Have you tried plating some of your proof coins? I'm really curious as to how a proof plated post-strike will come out looking. Thanks. >>
I have not plated any polished proof surfaces. But I think I have seen examples of medals that were. Whenever you see a token or medal where portions of the design elements are gold plated, while other areas are not, this is an example of "selective" gold plating. This type of plating is almost always done after striking.
<< <i>Some of the gold denomination U.S. pattern issues have even been glided after they were issued by the mint by early collectors who either wanted them to look like gold or just to protect them.
This SC$1 is a HK unlisted variety for having been struck on a gilt planchet. It was definitely struck on a gilt planchet instead of gilded afterward. With a 10x loupe you can actually see white ghosting within the patina on the lower reverse "Commenced & Finished" from each repeated strike. You can see a ghost “C” to the left of the “C” in Commenced and another “C” below the main “C”. This ripple or shock wave effect from each repeated die strike continues down to the rim with both words and dates "Commenced & Finished". Due to William Key's high relief design I can actually count that it’s been struck a minimum of 4 times. Sorry I'm not able to show more details as proof type issues are tough for me to photograph. When directly angled into a light source they entire fields on this medal become fully deep proof like, the patina vanishes, and the ghosting can be more easily seen.
>>
Nice medal.
I wouldn't automatically assume that it was plated prior to striking, however. Work-hardening of the medal during repeated striking might affect how readily gold bonds to some areas - just like how Morgan Dollars sometimes are less likely to tone in the higher-stressed areas next to letters near the rim.
<< <i>Awesome images Dan. Have you tried plating some of your proof coins? I'm really curious as to how a proof plated post-strike will come out looking. Thanks. >>
I have not plated any polished proof surfaces. But I think I have seen examples of medals that were. Whenever you see a token or medal where portions of the design elements are gold plated, while other areas are not, this is an example of "selective" gold plating. This type of plating is almost always done after striking. >>
Hi Dan, thanks. Do you have any hypotheses about what a proof coin would possibly look like if it were entirely plated by gold post-striking? For example, the OP's coin. I assume there would be absolutely no chance for a CAM/DCAM designation due to the plating. Could you shed some light onto this.
<< <i>Awesome images Dan. Have you tried plating some of your proof coins? I'm really curious as to how a proof plated post-strike will come out looking. Thanks. >>
I have not plated any polished proof surfaces. But I think I have seen examples of medals that were. Whenever you see a token or medal where portions of the design elements are gold plated, while other areas are not, this is an example of "selective" gold plating. This type of plating is almost always done after striking. >>
Hi Dan, thanks. Do you have any hypotheses about what a proof coin would possibly look like if it were entirely plated by gold post-striking? For example, the OP's coin. I assume there would be absolutely no chance for a CAM/DCAM designation due to the plating. Could you shed some light onto this. >>
I will try a test in the next few days - plating half of a modern proof coin. I believe that it will still look like the same cameo proof afterwards - just a different color overall.
The OP coin in this thread looks cleaned to me. Cleaning and/or heavy toning will certainly reduce cameo contrast. I do not believe thin gold plating will reduce cameo contrast.
<< <i>I don't see how it's possible to gilt the coin/planchet before striking and still get a satisfactory coin. Since the gilt is microscopically thin, the metal deformation and movement during striking would tear the gilt layer resulting in the base metal showing through on the surface of the coin. >>
I have seen Proof copper-plated zinc Lincoln cents where the copper plating is torn to the right and bottom of the S mint mark by the outward metal flow during the strike, exposing the zinc.
On the Soho piece, since it is a multiple-struck Proof, is it possible that the piece was struck 2 or 3 times to bring up the relief, gilt, and then given a final strike from the dies to give it the cameo finish? This would reduce metal flow during the final strike to practically nothing.
Numismatist. 50 year member ANA. Winner of four ANA Heath Literary Awards; three Wayte and Olga Raymond Literary Awards; Numismatist of the Year Award 2009, and Lifetime Achievement Award 2020. Winner numerous NLG Literary Awards.
Ed62
Posts: 857 ✭✭
Comments
<< <i>Help me. What does "gilt" mean in numismatic terms? At first, I thought is was left over Hanukkah candy, but that's "gelt". Then it's not a former male horse, either. Did the coin do something wrong (no, that's guilt)? >>
"Gilt" or "gilding" is a the application of a very thin layer of precious meta, in this case gold, that gives this pattern coin the appearance of what it would look like if it were sold gold.
<< <i>Obviously I'm out of my league here, and I was trying to be humorous before, but with the answer Bill gave me, it would seem that the original coin was not gold, but was "gilt" after minting. Could it be gold and needed an extra layer after minting to look good? Was this pattern coin made out of some other metal that someone "gilt" to make it look like gold? >>
It was very common for the mint to strike patterns for gold coinage in materials that cost much much less than gold and then simply gilt it. This coin is copper.
Beautiful and very historic pioneer gold piece.
<< <i>Ed62 - I've wondered the same about this coin - looking forward to seeing some answers, if offered.
Seriously? If so, I'd start by asking Kagin. Your piece is ex Robert Bass and it's plated in that catalog.
<< <i>Can a coin be 'Cameo' if it is gilt after it is struck? >>
Interesting, I hope someone can answer this.
Copper is not the only material that has been gilt. There are aluminum gilt ones too. Which is odd because back then aluminum was just about as spendy as gold.
<< <i>Someone more familiar with minting and striking may know but I would think that the pressure required to strike up a coin would totally obliterate the uber-thin layer of gilt. >>
Agreed, but at the same time, how would gilting a coin after striking it result in a cameo effect? I can see the entire surface having mirrors by the gilt but it seems unlikely that the devices will have mint "frost" on them.
Now that my focus isn't so tightly restrictive, that sure would be nice to have in my Box of 20.
They sure as heck weren't minted, and the gilt application takes on all of the underlying detail.
From the picture (above) it looks certain Lordmarcovan's gilt penny had its planchet gold-plated first and then the coin was struck with cameo dies.
<< <i>They sure as heck weren't minted, and the gilt application takes on all of the underlying detail. >>
Interesting, yes I have seen plated jewelry where the gold plating forms all the pockmarks of the metal underneath, but is it possible for the gold to take on all the miniscule flow lines that give the coin P/L surfaces and the frosty devices? I wouldn't doubt the gold would take on nuances of the underlying surfaces, but I would still think it would exhibit the flashy reflectiveness of plated gold throughout the entire coin irregardless of how the metal is underneath.
Worry is the interest you pay on a debt you may not owe.
<< <i>This is mine. I have zero photo skills but I can scan with the best of them. If there are any parts anyone would like to see at higher resolution that might help prove one way or another how these things come to be, I can do that. >>
Hi,
Is the coin CAM/DCAM? If so, how do the devices look in hand? Are they frosty like a proof gold coin or flashy throughout? Thanks.
<< <i>I don't see how it's possible to gilt the coin/planchet before striking and still get a satisfactory coin. Since the gilt is microscopically thin, the metal deformation and movement during striking would tear the gilt layer resulting in the base metal showing through on the surface of the coin. >>
I concur. The stamping process requires melting the top layer of metal to get it to flow into voids in the die.
Slabbed Gold For Sale
<< <i>
<< <i>I don't see how it's possible to gilt the coin/planchet before striking and still get a satisfactory coin. Since the gilt is microscopically thin, the metal deformation and movement during striking would tear the gilt layer resulting in the base metal showing through on the surface of the coin. >>
I concur. The stamping process requires melting the top layer of metal to get it to flow into voids in the die. >>
I don't believe they melt it, they merely heat up the planchet and then wash it before upsetting the rims and then it goes straight to striking. The melting points of gold and copper are pretty close.
Yep - I bought 6 coins or so from that collection when it was broken up.
The planchet was unquestionably gilt.
So, I'm pretty certainly that at least some pieces were gilt before being struck.
what is your thinking on how the gilding is done??
It is very intuitive, IMHO.
I firmly believe in numismatics as the world's greatest hobby, but recognize that this is a luxury and without collectors, we can all spend/melt our collections/inventories.
eBaystore
<< <i>what is your thinking on how the gilding is done?? >>
I'm thinking that we really need a metallurgist to weigh in here.
I'm thinking that it would also be a great opportunity for our hosts to share some of their experience, if they choose to. I know that I've seen plenty of pieces from across the street, both slabbed and unslabbed, where I could only wonder how they came to their conclusions .The grading services are making tis decision, somehow.
Beyond that... we've had plated Lincoln cents for almost 30 years and after they worked out the kinks in the first year or two I can't think of the last time I saw torn plating on a normally struck coin (errors don't count here). It's clearly possible to strike plated planchets with good quality in the finished product, even if I don't know how it's done.
<< <i>The planchet was unquestionably gilt.
So, I'm pretty certainly that at least some pieces were gilt before being struck. >>
Because you own a gilt planchet (which is way cool BTW) does not necessarily mean that the planchets were gilded and then struck. The fact that that exists could simply have been the result of a process to test the reaction of the base metal with the gilt to see how it would hold up. And yes it very well could have been struck, but the existence of a gilt planchet does not automatically mean that it was subsequently struck.
<< <i>
<< <i>I don't see how it's possible to gilt the coin/planchet before striking and still get a satisfactory coin. Since the gilt is microscopically thin, the metal deformation and movement during striking would tear the gilt layer resulting in the base metal showing through on the surface of the coin. >>
I concur. The stamping process requires melting the top layer of metal to get it to flow into voids in the die. >>
I've personally minted both types:
A) Gold-plated prior to striking.
Both will work, and it is not generally possible to distinguish one from the other.
The layer of gold (typically from electro-plating) is very thin. But this layer will stretch considerably. The gilt layer does NOT "tear" or leave gaps or voids upon striking. And the top surface of the struck coin does NOT melt. In fact, normally-struck coins that I drop into my hand the instant after they are struck do not even feel warm.
Whatever surface texture a coin has will usually be preserved after electro-plating. The only exception is a toned coin (the electro-plating acids will react with the oxidized metal). So if a coin has an un-toned proof finish, it will still have that same finish after electro-plating.
Here is a coin that was gold-plated prior to over-striking:
I do not have a picture handy of a coin that I plated after striking, but I will try and take one and post it here.
Worry is the interest you pay on a debt you may not owe.
This SC$1 is a HK unlisted variety for having been struck on a gilt planchet. It was definitely struck on a gilt planchet instead of gilded afterward. With a 10x loupe you can actually see white ghosting within the patina on the lower reverse "Commenced & Finished" from each repeated strike. You can see a ghost “C” to the left of the “C” in Commenced and another “C” below the main “C”. This ripple or shock wave effect from each repeated die strike continues down to the rim with both words and dates "Commenced & Finished". Due to William Key's high relief design I can actually count that it’s been struck a minimum of 4 times. Sorry I'm not able to show more details as proof type issues are tough for me to photograph. When directly angled into a light source they entire fields on this medal become fully deep proof like, the patina vanishes, and the ghosting can be more easily seen.
Earlier in his tome he discusses restrikes by Taylor which used prepatinated blanks, and on page 226 states that " the process of striking on pre-gilded and pre-patinated bronze blanks was Boultons invention". Much research has taken place on the earlier (1672-1775) gilt and bronzed British coins and the majority opinion is that these are all later additions to currency coins. For example there are many early farthing pieces from Charles 1 through Anne that are silver plated, and whether done by the mint or not it seems to me that these were all done post striking.
Personally I am convinced that the genuine early pieces (beginning with Soho mint) were gilt or bronzed prior to striking, although there are quite a few (fakes/restrikes/call them what you will) that were done post striking.
Early Soho Gilt proofs:
Bronzed proof
World Collection
British Collection
German States Collection
.......................nice medal, Frank!!
<< <i>so it seems clear that Gilding was done both before as well as after striking coins/medals, but what of the process itself?? can anyone enlighten the forum about how it's done.
.......................nice medal, Frank!!
Gold plating solution has two formulas: cyanide based and acid-based.
With either type, the item to be plated is connected to a negative terminal (cathode). This is the terminal that attracts positively charged (+) ions.
The item is submerged in the solution containing dissolved gold. The positive terminal (anode) is placed into the solution, but not touching the object. A voltage is applied across the terminals (typically 2 to 12 volts DC).
Positively-charged gold ions are attracted to the cathode (which is essentially the item being plated). When the gold ions contact the object, they "grab" an electron and bond to the object and form a coating of gold.
<< <i>Awesome images Dan. Have you tried plating some of your proof coins? I'm really curious as to how a proof plated post-strike will come out looking. Thanks. >>
I have not plated any polished proof surfaces. But I think I have seen examples of medals that were. Whenever you see a token or medal where portions of the design elements are gold plated, while other areas are not, this is an example of "selective" gold plating. This type of plating is almost always done after striking.
<< <i>Some of the gold denomination U.S. pattern issues have even been glided after they were issued by the mint by early collectors who either wanted them to look like gold or just to protect them.
This SC$1 is a HK unlisted variety for having been struck on a gilt planchet. It was definitely struck on a gilt planchet instead of gilded afterward. With a 10x loupe you can actually see white ghosting within the patina on the lower reverse "Commenced & Finished" from each repeated strike. You can see a ghost “C” to the left of the “C” in Commenced and another “C” below the main “C”. This ripple or shock wave effect from each repeated die strike continues down to the rim with both words and dates "Commenced & Finished". Due to William Key's high relief design I can actually count that it’s been struck a minimum of 4 times. Sorry I'm not able to show more details as proof type issues are tough for me to photograph. When directly angled into a light source they entire fields on this medal become fully deep proof like, the patina vanishes, and the ghosting can be more easily seen.
Nice medal.
I wouldn't automatically assume that it was plated prior to striking, however. Work-hardening of the medal during repeated striking might affect how readily gold bonds to some areas - just like how Morgan Dollars sometimes are less likely to tone in the higher-stressed areas next to letters near the rim.
<< <i>
<< <i>Awesome images Dan. Have you tried plating some of your proof coins? I'm really curious as to how a proof plated post-strike will come out looking. Thanks. >>
I have not plated any polished proof surfaces. But I think I have seen examples of medals that were. Whenever you see a token or medal where portions of the design elements are gold plated, while other areas are not, this is an example of "selective" gold plating. This type of plating is almost always done after striking. >>
Hi Dan, thanks. Do you have any hypotheses about what a proof coin would possibly look like if it were entirely plated by gold post-striking? For example, the OP's coin. I assume there would be absolutely no chance for a CAM/DCAM designation due to the plating. Could you shed some light onto this.
I knew it would happen.
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<< <i>Awesome images Dan. Have you tried plating some of your proof coins? I'm really curious as to how a proof plated post-strike will come out looking. Thanks. >>
I have not plated any polished proof surfaces. But I think I have seen examples of medals that were. Whenever you see a token or medal where portions of the design elements are gold plated, while other areas are not, this is an example of "selective" gold plating. This type of plating is almost always done after striking. >>
Hi Dan, thanks. Do you have any hypotheses about what a proof coin would possibly look like if it were entirely plated by gold post-striking? For example, the OP's coin. I assume there would be absolutely no chance for a CAM/DCAM designation due to the plating. Could you shed some light onto this. >>
I will try a test in the next few days - plating half of a modern proof coin. I believe that it will still look like the same cameo proof afterwards - just a different color overall.
The OP coin in this thread looks cleaned to me. Cleaning and/or heavy toning will certainly reduce cameo contrast. I do not believe thin gold plating will reduce cameo contrast.
<< <i>I don't see how it's possible to gilt the coin/planchet before striking and still get a satisfactory coin. Since the gilt is microscopically thin, the metal deformation and movement during striking would tear the gilt layer resulting in the base metal showing through on the surface of the coin. >>
I have seen Proof copper-plated zinc Lincoln cents where the copper plating is torn to the right and bottom of the S mint mark by the outward metal flow during the strike, exposing the zinc.
On the Soho piece, since it is a multiple-struck Proof, is it possible that the piece was struck 2 or 3 times to bring up the relief, gilt, and then given a final strike from the dies to give it the cameo finish? This would reduce metal flow during the final strike to practically nothing.