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Author Topic:   Please explain mercury gilding to me
Jane Straub
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iconnumber posted 06-26-2005 08:01 PM           Edit/Delete Message   Reply w/Quote
Mercury guilding was the 18th century process of applying gold to silver. I understand this process was hazardous. Where can I find a discription of how it was done or can some explain it to me. Also, is there any risk associated with using 18th century items which have been guilded? (don't think so)Thank you.

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wev
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iconnumber posted 06-26-2005 08:11 PM     Click Here to See the Profile for wev     Edit/Delete Message   Reply w/Quote
The technique was not difficult -- an amalgam of gold and mercury was made up and applied to the base metal. It was then fired at high heat, burning off the mercury, and leaving a thin, precise, and consistent layer of gold. The danger is obvious when done in a small poorly ventilated shop using an open hearth or oven.

The risk of using such pieces is generally low, though a small percentage of mercury may be left, if done imperfectly.

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Jane Straub
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iconnumber posted 06-26-2005 08:14 PM           Edit/Delete Message   Reply w/Quote
If the mercury was burned off in the process it certainly was a hazard to whoever was the craftsman. Thank you.

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Dale

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iconnumber posted 06-26-2005 11:57 PM     Click Here to See the Profile for Dale     Edit/Delete Message   Reply w/Quote
Not only the craftsman, but everyone in the general area. And beyond.

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Jane Straub
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iconnumber posted 06-27-2005 11:05 AM           Edit/Delete Message   Reply w/Quote
Guess I am overreacting but is there any way to be certain all mercury as been removed? Like does a good washing do it ? Or, should one assume that over 200 yrs the mercury is all gone. Just seems a shame not to use an 18th c. berry spoon because of fears of the guilding.

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ahwt

Posts: 2334
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iconnumber posted 06-27-2005 11:58 AM     Click Here to See the Profile for ahwt     Edit/Delete Message   Reply w/Quote
Below is a thread that discusses mercury.
mercury gilding

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Silver Lyon

Posts: 363
Registered: Oct 2004

iconnumber posted 06-27-2005 05:34 PM     Click Here to See the Profile for Silver Lyon     Edit/Delete Message   Reply w/Quote
I have teo little spanners to throw into the works of this thread.
  • There is no such thing as an c.18th Berry Spoon - pieces purporting to be that are c.18th pieces altered either in the mid-c.19th (best senario) or c.20th and even c.21st - it is easy to take a tablespoon with a worn bowl and stretch the bowl and stamp in the design with fruit etc. and then cover up the discolouration with either silver-plate or gilding.

    Such pieces are available wholesale in London and New-York, newly created.

    Thus a beautiful (and valuable) berry spoon rises phoenix-like from the remains of a worn-out spoon only good for melting down.

This brings me to my second spanner...

  • Being an at best c.1860 concoction, the berry spoon with eighteenth century marks will have electro-gilding (a process in which the gold is deposited electronically from a solution containing cyanide) - so no risk of mercury poisoning!. The residual cyanide, if any is washed off with acid before the piece is 'finished' - so no risk of cyanide poison either.
    Eat your berries in peace!
Enjoy your spoon(s) they represent an interesting example of how adaptable silver is to the whims of fashion! smile

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Clive E Taylor

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iconnumber posted 06-27-2005 06:47 PM     Click Here to See the Profile for Clive E Taylor     Edit/Delete Message   Reply w/Quote
Very little risk now of mercurial gilding as the mercury is used as a flux and I believe virtually all is volatised in the process.

But watch some NON SILVER Buckles. I recently experimented with a non silver buckle which had a form of - I thought - of oxidised lead/ pewter decoration almost piped on like icing a cake . It's a fairly common type to find. I discovered that the melting point was very low, and yes it seems to have been applied and shaped whilst molten. This I discoved by applying a blowtorch producing fumes and leadlike beads of metal

Chemical analysis by a competent and careful chemist (unlike me) proved it to have a very significant amount of ANTIMONY in it. Guess what the fumes were ! I'm still alive but apparently my life expectancy is slifghtly less now !!
Clive

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Antiqueperson

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Registered: Jun 2005

iconnumber posted 06-28-2005 01:05 AM     Click Here to See the Profile for Antiqueperson     Edit/Delete Message   Reply w/Quote
Thank you for the information. This takes us into the whole realm of hazardous antiques and how paranoid and/or careful we should be with them. My paranoia extended to removing a Queen Anne mirror to the garage for several weeks (fear of the painted mirror), throwing out a batch of glasses (fear they were lead crystal) and buying a pewter funnel and freaking out when I realized 18c. pewter has a high lead content(but never actually used it). Oh, forgot all the Victorian holiday decorations I won't take out of the box.

So my question is, what does a genuine 18th cent. berry spoon look like? How can you tell the difference?

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Silver Lyon

Posts: 363
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iconnumber posted 06-28-2005 02:23 AM     Click Here to See the Profile for Silver Lyon     Edit/Delete Message   Reply w/Quote
    THERE IS NO SUCH THING as a genuine eighteenth century berry spoon!

See my note above.

Genuine nineteenth century examples, made new in the nineteenth century, have the appropriate marks for when and where they were made.

Conversions, which were (are) cheaper as the 'old' spoon was (is) already in existence, have the marks that they started with when they were made originally.

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Antiqueperson

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Registered: Jun 2005

iconnumber posted 06-28-2005 09:10 AM     Click Here to See the Profile for Antiqueperson     Edit/Delete Message   Reply w/Quote
But there are Georgian Berry Spoons, made @1810 which are hollow sterling and the form of the item is such that it could not be later stamped with decoration. The construction of the item is such it would not look right if made that way. And they are called, 'Georgian Berry Spoons.' I can't believe everything is a fake out there.

It seems to me that some folks on this forum are only happy with an 18c. item and think it is genuine if it looks Provincial or worn out .

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Antiqueperson

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iconnumber posted 06-28-2005 10:05 AM     Click Here to See the Profile for Antiqueperson     Edit/Delete Message   Reply w/Quote
I mean, there are entire chapters in silver books on silver Hollow Ware of the early 19th century. BUT, come to think of it, I have never seen berry spoons in the silver section of a great art museum, but always thought that may be due to the fact they have such grand items of craftsmanship to display.

When I actually look at the luxury and grandeur of many aspects of late 18th century life, and the sophistication of thought, I would be surprised there were no fancy Georgian Berry Spoons then.It would mean the craft was not sophisticated enough to create them at that time. From what I see, the craft was that sophisticated.

I think it would be good to support a statement like Georgian Berry Spoons do not exist, that is, spoons of floral and fruit design created in the early 19th century.

Please don't misinterpret me, I very much want to be enlightened here. But it seems that 18th c. items are called a 'fake' in this forum if they are anything but Provincial . Just seems like that to me as a newcomer.

ps.
Sorry to start the new topic- I thought that would be correct as the focus had shifted from gilding to Berry Spoons.

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Scott Martin
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iconnumber posted 06-28-2005 10:33 AM     Click Here to See the Profile for Scott Martin     Edit/Delete Message   Reply w/Quote
quote:
ps. Sorry to start the new topic- I thought that would be correct as the focus had shifted from guilding to Berry Spoons.

It's the right idea. Next time start the new thread before it develops as much as it did in this existing thread. Also clue the existing thread posters and lurkers in by directing them to the new topic post/thread. Your new post/thread read like a reply to comments in this exiting thread and by itself the new thread/post was floating with an implied but no direct reference back to this existing thread. Posts/thread are long lived and in a few years the connections would be lost on new readers.

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akgdc

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iconnumber posted 06-28-2005 10:43 AM     Click Here to See the Profile for akgdc     Edit/Delete Message   Reply w/Quote
What books are you reading? They also seem to be misinformed about the definition of hollowware. Spoons are flatware.

There is NO such thing as an 18th-century "berry spoon." Also no such thing as an 18th-century paper-clip holder, salad spinner, ice-cream scoop, toilet scrubber, or refrigerator magnet, either. Oh, that poor benighted century.

Again, if you have questions about specific pieces, please post photos. If you need instructions on doing that, click here: How to post photos

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Antiqueperson

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iconnumber posted 06-28-2005 10:57 AM     Click Here to See the Profile for Antiqueperson     Edit/Delete Message   Reply w/Quote
I asked for you to support your statement first.

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akgdc

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iconnumber posted 06-28-2005 11:34 AM     Click Here to See the Profile for akgdc     Edit/Delete Message   Reply w/Quote
SilverLyon gave a thorough and well-informed response. And this topic has been dealt with numerous times previously in these forums, for instance:

William Holmes?

Beyond that, just look in any reputable book on English flatware. I don't know what more you want, short of an entry in Hester Bateman's diary stating something like, "July 12th, 1788. Berry spoons have still not been invented."

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Richard Kurtzman
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iconnumber posted 06-28-2005 11:51 AM     Click Here to See the Profile for Richard Kurtzman     Edit/Delete Message   Reply w/Quote
Hi Everbody. Who's on first?

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Antiqueperson

Posts: 18
Registered: Jun 2005

iconnumber posted 06-28-2005 12:03 PM     Click Here to See the Profile for Antiqueperson     Edit/Delete Message   Reply w/Quote
Thank you for the references. I will check them out.You have to understand- I can't just believe someone who says something without giving support for their statement- like, 'it's so because Tommy SAID so.' If you get my drift. But I also fully understand the cummulative effect of knowledge of a subject too. I understand when people 'feel' an object isn't 'right'. What I look for are those folks who can articulate why the feel isn't right.

I am a new member and truly appreciate the kind and welcoming words by many on this forum. I do not scare off or abandon positions easily and I often need references and support for blanket statements made to me. There are many very kind folks here who understand where I am coming from and understand the learning process. If anyone (akgdc)does not care to engage in a conversation with me, that's fine! But, I have just interests here too! Have a great day!

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swarter
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iconnumber posted 06-28-2005 12:38 PM     Click Here to See the Profile for swarter     Edit/Delete Message   Reply w/Quote
Jane:
quote:
Hello,.. I think I can speak for myself.

quote:
It seems to me that some folks on this forum are only happy with an 18c. item and think it is genuine if it looks Provincial or worn out.

quote:
I asked for you to support your statement first.

You seem unwilling to accept that you have been given patient, authoritative answers (some of which do not fit your preconceived notions) by informed contributors attenmpting to answer your questions, which they are not obligated to do. Are you here to argue or to learn? Please read the section on proper forum etiquette in the Guidelines.

Incidentally, "guilding" is "gilding," and "soulder" is "solder."

You really do have a lot to learn.

--------------------

quote:
If anyone does not care to engage in a conversation with me, that's fine!

People donate their time to answer questions here - they do not have the time to write a thesis for every repetitious question - if you would have first taken the trouble to have used the forums' search engine on "mercury", or "gilding" or "mercury gilding," you would have found prior discussions which might have answered your question without having to ask at all, or to have asked more informed questions based on the prior information. The same goes for "berry spoons."

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Kimo

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iconnumber posted 06-28-2005 04:36 PM     Click Here to See the Profile for Kimo     Edit/Delete Message   Reply w/Quote
Dear Antiqueperson,

Before this spins out of control with misunderstandings and ensuing hard feelings, please let me say that since you are new to the forum you may not understand yet who these people are who have given you these answers. They are some of the most experienced and learned folks around in the area of silver collecting. I know that on some other forums there is an abundance of people who have few facts answering questions and your insistence on grilling responders about their answers would be reasonable in those kinds of places. If you lurk here a while you will soon see that the people who have taken the time to give you your answers are true experts. Your questions are asked in a way that uses phrasing that inadvertently comes across to many as strident which gives most people the impression of your not being very appreciative of their generosity.

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Silver Lyon

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iconnumber posted 06-29-2005 06:11 AM     Click Here to See the Profile for Silver Lyon     Edit/Delete Message   Reply w/Quote
Even at this horribly early, but blessedly cool, time of the morning it is reassuring that so many members of the forum feel protective towards the 'body' - everyone who contributes, whether experienced or new does so with an open hand. There is no personal gain to be derived from contributing.

I fear that any of us can sound arrogant at times trying to express in few words things that appear obvious to us and experience that has been learned and gathered over many years.

Berry spoons are alterations, not fakes - they can be misleading because they still have their original marks. Please believe me, THERE ARE NO GEORGIAN ONES made as such.

Any experienced dealer who tells you differently is being disingenuous.

Published sources for discussions of alterations and improvements to silver are few and far between, but the subject (Berry Spoons) is covered in Ian Pickford's admirable book "Silver Flatware, English, Scottish and Irish 1660-1980" published by the Antique Collector's Club, Suffolk, England.

The Antique Collector's Club, also published a piece many years ago in their magazine Antique Collecting they may have an index and a back-issues department.

Many of the people who contribute to the forums are those who WRITE the books, CURATE the museum collections, GIVE the lectures - they are here to HELP and INFORM and INSPIRE those who SHARE their interest in a subject they find fascinating. wink

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Antiqueperson

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iconnumber posted 06-29-2005 08:38 PM     Click Here to See the Profile for Antiqueperson     Edit/Delete Message   Reply w/Quote
Silver Lyon is articulate and presents his information in such a way that is not offensive. Thank you SilverLyon! I understand you clearly!

Silver Lyon, So, the Batemans made no Berry Spoons? I mean, you can call an item a Georgian Berry Spoon but to do so is really a misnomer, it only indicates the hallmarks are Georgian- right?

Please don't speak on my behalf anyone.I can speak for myself.

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salmoned

Posts: 336
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iconnumber posted 06-29-2005 10:43 PM     Click Here to See the Profile for salmoned     Edit/Delete Message   Reply w/Quote
You're not REALLY asking a question that's been answered so well already again, Are you? I'm absolutely positive your last question was rhetorical in nature - and yet that can only be an opinion, at best. In any case, I don't think berry spoons were beyond the capabilities of 18th century craftsmen - it was merely beyond the sensibilities of the buying public to want such a thing. In fact, I doubt anyone here could categorically state that no berry spoon as it is now recognized was ever created in the 18th century. Only that, they are rare to the point of non-existence. wink

Oh, this is fun!

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Antiqueperson

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iconnumber posted 06-30-2005 07:53 AM     Click Here to See the Profile for Antiqueperson     Edit/Delete Message   Reply w/Quote
Interesting. You have to realize, I'm a layman. (and that's why I'm in this forum!)I don't have a lot of intricate knowledge of 'silver'. All I know is, I rarely see very old berry spoons- that is berry spoons with old hallmarks. Maybe they are sold by the barrelfull in N.Y.C. or London- but I haven't see them.

So , what do decorative 18th Century spoons look like? You can discribe, links or photos not necessary. Thanks!

Please understand , I'm trying to illicite Conversation. Photos, etc. not necessary, just articulation!Thanks a bunch!

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Antiqueperson

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iconnumber posted 06-30-2005 07:57 AM     Click Here to See the Profile for Antiqueperson     Edit/Delete Message   Reply w/Quote
And I sincerely apologize for any misspellings.I'm not very computer literate and you don't have to shame me for it.

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ahwt

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iconnumber posted 07-01-2005 12:33 PM     Click Here to See the Profile for ahwt     Edit/Delete Message   Reply w/Quote
This is an interesting thread for me as it recalls to me the many times that I reviewed patents involved in infringement cases and initially thought; “This is a simple idea, surely I can find a publication that discloses this same design by someone at a earlier time.” Most or the time I found out that the U.S. Patent Office really did a good job in reviewing the prior art and I did not find an earlier work that could be used to invalidate the patent. Not finding a printed publication does not prove that that the idea had not been thought of at an earlier time, but rather shows that if someone did have the idea it was not implemented or recorded in any significant manner. This may be the case with berry spoons. It could be that some forward thinking person thought of portraying an image of berries of the face of the bowl of a spoon during the Georgian time period. However, I am not aware of any evidence recording either this idea or implementation of this idea.

The March/April 2002 issue of Silver Magazine has an interesting article by D. Albert Soeffing that shows how information about designs used in different time periods can be found in unusual places. Here a letter written in 1833 discloses that the style of Old English was chosen for a monogram by a gentleman living in Kentucky. This was at a time period when the prevailing style of engraving was an italic script and backs up in time when Old English could have been used on silver in America. It also provides an insight into what Kentuckians thought of breaking with the prevailing style and trying something new.

This is a good illustration of why the study of silver is interesting to me. These studies provide a real connection with the past and in that sense make the past come alive.

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Scotia

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iconnumber posted 07-01-2005 12:52 PM     Click Here to See the Profile for Scotia     Edit/Delete Message   Reply w/Quote
Hi there,

Late 18th century spoons were commonly decorated with bright cut engraving, a method of decoration leaving many facets, which reflect light. Please see this link for a better explanation: Antique Silver Spoons

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Antiqueperson

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Registered: Jun 2005

iconnumber posted 07-02-2005 09:00 AM     Click Here to See the Profile for Antiqueperson     Edit/Delete Message   Reply w/Quote
Thank you for the link and enlightening me! Bright Cut, I have seen the marvelously intricate 18th. C Bright cut sugar tongs and nips. But have never seen a Georgian Berry Set. Thanks again!!!

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Scott Martin
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iconnumber posted 05-20-2017 03:20 PM     Click Here to See the Profile for Scott Martin     Edit/Delete Message   Reply w/Quote
MIT science paper:

Ancient Methods of Gilding Silver :
Examples from the Old and the New Worlds

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Vetdaddy

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iconnumber posted 06-05-2017 02:45 PM     Click Here to See the Profile for Vetdaddy     Edit/Delete Message   Reply w/Quote
Good read- thanks Scott. I suppose the early metal-smiths may have have also been afflicted with 'mad hatters' disease.

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Scott Martin
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iconnumber posted 06-06-2017 12:29 AM     Click Here to See the Profile for Scott Martin     Edit/Delete Message   Reply w/Quote
Glad you liked it. Its more info (words) than most people have patience for (29 pages) smile

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Scott Martin
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iconnumber posted 06-06-2017 01:54 AM     Click Here to See the Profile for Scott Martin     Edit/Delete Message   Reply w/Quote
THE JEWELERS’ CIRCULAR
July 6, 1904
pg 74
July 13, 1904
pg 74

quote:
Mercury Gilding and Its Injurious Effects on the Operator

Owing to differences in the chemical properties of metals it is possible to deposit one metal upon another by simply immersing the metal to be coated in a properly prepared solution of the metal which it is desired to deposit. A very simple example of this is found in the deposition of copper upon iron. If a little copper sulfate is dissolved in water and a few drops of sulfuric acid are added, a piece of clean iron immersed therein will immediately be covered with a deposit of copper. The metal, however, is only loosely adherent. The explanation of the action is that the iron, being chemically stronger than the copper, is able to replace it in the sulfate solution. Iron sulfate is formed and an equivalent quantity of copper is deposited upon the remaining iron. The action would continue until the whole of the iron had been dissolved or the whole of the copper had been deposited from the solution. With some solutions, however, when a thin, firmly adherent case has been deposited, the metal underneath is protected and further action ceases. It is only when this is the case that the process is of practical utility. The process known as water gilding is based upon the above property. A solution for depositing gold may be made as follows: 6% dwts. of fine gold are dissolved in nitro-hydrochloric acid and the pure gold chloride is obtained. This is dissolved in water and one quart of the solution is made. One pound of bisulphate of potash is then added and the mixture is boiled for two hours. At the end of this time it has changed from yellow to green and is ready for the gilding process. The articles to be gilded are thoroughly cleansed. If they are of copper or brass they are simply immersed in the solution for half a minute. If German silver is subjected to the process a piece of sheet zinc must be placed in contact with the article during immersion. The article is then taken out and well swilled in water, when it is found to have received a fairly coherent but thin coating of gold. The next mode of gilding is that of mercury gilding. This is a process which is now almost obsolete. It is interesting. however, as it was much used before the introduction of electro-deposition.

Whatever may be said to the contrary, mercury gilding has merits which electro gilding can never surpass. The process of mercury gilding is based on the fact that mercury readily forms an amalgam with gold. When the amalgam is strongly heated the mercury is driven off in the form of vapor, leaving the gold behind. The amalgam is made by heating fine gold or a gold alloy to a low red heat in a crucible, and then adding eight times its weight of mercury. The mass is kept hot and stirred with an iron rod until the gold is dissolved. The amalgam is then poured in a shallow dish containing water and worked with the fingers to expel the excess of mercury. The pasty mass thus obtained is squeezed in wash leather to remove a further proportion of the fluid mercury, and is then ready for use. The expelled mercury contains gold and is used to prepare a fresh quantity of amalgam.

The amalgam is placed on a flat stone, and the work to be gilded, after having been thoroughly cleansed and dried, is carefully coated with it. This is effected by means of a brass wire brush, which is first dipped into a solution of nitrate of mercury (made by dissolving mercury in moderately strong nitric acid and diluting the solution with 20 times its volume of water), then rubbed over the amalgam and finally over the work. The operation is continued until a satisfactory coating is obtained. The article, after having been swilled in water, is held over a charcoal fire and tapped gently to keep the amalgam uniformly distributed over the surface.

The article, when sufficiently heated, is allowed to cool, after which it is scratch brushed. It is again heated in order to expel the last traces of mercury. If any parts do not appear to be properly coated they are touched up with the amalgam before heating the second time. The article is now ready to be burnished or colored by the wet or dry coloring process, as desired. It is very difficult to avoid inhaling the mercury vapor during the process and on that account the process is a very unhealthy one, except special contrivances are used.

An amalgam for gilding small articles or repairing the injured parts of larger objects may be conveniently prepared in the following manner: Place one part of leaf gold in a small iron saucepan or ladle, perfectly clean, then add about eight parts of mercury and apply a gentle heat, when the gold will dissolve; agitate the mixture for one minute and pour it out on a clean plate or stone slab. When cold it is ready for use. With the introduction of the mode of gilding by electro-deposition mercury gilding came into disrepute. But with all discoveries in that new line of depositing gold on other metallic surfaces, fire gilding has not been entirely superseded, as it has certain advantages. The injurious effects of inhaling the fumes of the evaporating quicksilver during the process of fire gilding have been brought forward as a deterring reason for not practicing fire gilding. As nearly all new and important discoveries entering into manufacturing processes beget a certain enthusiasm, and cause us to abandon and discard the old. in a most reckless manner, it is reasonable to surmise that this has been the case with mercury gilding and silvering.

Mercury is one of the most useful metals and at the same time a metal very destructive to human life, when not handled and utilized with intelligence and proper care. It is dangerous to handle in its natural metallic state, as it will evaporate and charge with its poisonous gas the surrounding atmosphere in a confined room at a normal temperature; workmen in quicksilver mines, men who coat looking glasses with a tin amalgam, men who fill thermometers and barometers, who make explosives and manufacture chemical compounds are often fatally poisoned by its gases, but it may be safely asserted that there is no case on record, as far as is known, of any individual having been fatally poisoned by mercury gilding. The agitation of the question had led to an investigation which shows that apparatus may be constructed by which the fumes which arise during quicksilver gilding may be collected. These apparatus have shown a very small percentage (less than five per cent.) of mercury lost in the process of fire gilding, and it is a question whether an ordinary jeweler’s furnace, with a good draught, would show a much more unfavorable result.


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Scott Martin
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iconnumber posted 06-06-2017 07:21 PM     Click Here to See the Profile for Scott Martin     Edit/Delete Message   Reply w/Quote
The Jewelers’ Circular and Horological Review.
FEBRUARY, 1884
pg 50-51

quote:
Electro-Fire Gilding and Silvering

COMPLAINTS AGAINST the durability of the ordinary electrogilding and silvering by contact or limited battery, and of the abrasion when exposed to wind and weather or friction, as compared to the good old fire gilding, are very frequent, although the former is generally acknowledged to have a richer appearance than the latter. The reason for the complaints are based upon the fact that the deposits of the precious metals by the galvano-electric system are not of a solid and compact nature.

Experience has taught that electro-gilt ornaments attached to churchyard monuments, lightning conductors, crosses, balls, eagles, etc., and other emblems of church steeples and public buildings, very soon tarnish, which is fully proved to be the cause of the un-solid and porous deposit of the gold on the metal forming the base of the articles.

To effect good substantial deposits of gold or silver by electricity, we are compelled to take recourse to batteries of great capacity, dynamo-electric apparatus worked by steam power, arrangements which to purchase and maintain entail expenses prohibitory to the jeweler or watchmaker who conducts his business on a limited scale, and who, if even in a position to purchase and maintain these expensive appliances, in very rare instances has sufficient work to realize a profit to warrant and encourage the outlay.

In order to overcome the instability of the deposit by electro-gilding, and to avoid the considerable expense of costly apparatus, while securing at the same time a good deposit by electricity, the following procedure is recommended as practically good and satisfactorily effective:

To the ordinary gold solution for electro-gilding add some mercury previously dissolved in nitric acid; this solution, diluted with water and neutralized of the acid by adding small quantities of spirits of ammonia until immersed litmus paper does not change its blue color into red. Previously to dissolving the mercury in the acid, it is necessary to free it from the lead with which commercial mercury is generally contaminated, and this is effected simply by pressing the mercury through a piece of wash-leather, which will allow the mercury to pass through on squeezing it, and retain the' lead.

This prepared gold solution will be a mercurial gold amalgam of a fluid or watery nature, and should not be mixed in larger quantities than required for immediate use. The articles to be gilt are immersed in this solution appended to the wire in connection with the cathode (zinc) of any battery, and will receive a gold deposit of quicksilver appearance after the article has remained a sufficient time in the solution. It is then withdrawn, rinsed in water and laid on a fresh fire made of small pieces of charcoal until the mercury has evaporated, which takes place very soon, as the quantity of mercury is very small in proportion to the gold deposit, although the color of the former predominates. After the evaporation of the mercury, the article has all the characteristics in color and toughness of fire-gilding, pale yellow and dead surface. The article is then scratch-brushed in beer and will assume a fine luster. If a strong deposit of gold is required the operation may be repeated after each scratch brushing. By weighing the article before the first immersion into the gold solution and again after the last scratch-brushing, the weight of the gold deposited can very accurately be ascertained. In the last evaporation the article is left for about half a minute or so longer on the fire than necessary for driving off the mercury, which will deepen the coior of the gilding.

After a final scratch-brushing, the article may be gilded in an ordinary gold solution without the addition of mercury, by which the richness of color of electro-gilding and the durability of fire gilding are combined.

This kind of gilding is accomplished with much less trouble, and, what is of great importance, attended with less or almost no danger than fire-gilding on the old method, which requires the continual handling of a large quantity of mercury so injurious to health, as the deposit of mercury in combination with the gold deposit in electro fire-gilding is so slight as to evaporate almost instantaneously, and affords the great advantage of a regular deposit of gold, not only on the surface but in the hollows and interstices of the article to be gilt. If any places or portions of the articles do not require gilding, they may be kept from being thus treated by a coating of copal varnish mixed with a little rouge powder and drying in a warm place before immersion in the gold solution.

The same method may be advantageously applied to electro firesilvering, by employing silver solutions, and the results are excellent.

Care must be taken that the mercurial gold or silver solutions are kept carefully apart from the ordinary gold and silver solution.

Silvering by fire has been very much neglected and preference given to electro-plating, but fire gilding is still practiced to a considerable extent, and the careful perusal of the above cannot fail to convince us that the combination of electro fire-gilding not only fully replaces the ordinary and antiquated process of fire-gilding, but effects at the same time a great saving of precious metal, which would unavoidably be lost in fire-gilding, while at the same time presenting all the advantages to be derived from that method.

— [H. Busch,Hull]


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