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Gold plating removal
Q. How (what chemical) can I use to remove the gold plating from an old watch?
Thomas Tomcik- Burlington, Vermont
A. Hi, Thomas. Since you don't say what the watch case is made of, or what kind of finish you want to apply to it, I'm guessing you trying to salvage the gold value of the watch?
The weight of gold per square foot for each millionth of an inch of thickness is .00147 troy ounces. If the watch is from the last couple of decades the gold is probably about 20 millionths of an inch thick (about half a micron): that's .0294 troy ounces per square foot. If the gold plated area is 2 square inches, it's .00041 troy ounces of gold. It's about 25 cents worth of gold for a relatively recent watch. But if it's a really old pocket watch, the plating is a hundred times thicker and it could easily contain a substantial amount of gold. Please clarify what you are trying to do. Thanks!
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Q. Hello, my name is Paul. I'm a student of Edinboro University of Pennsylvania Art Program. I do some gold, silver and copper plating. Some time I need to recover the gold plated on the "hoops" pieces. I need to know what chemicals I can use with rectifier type gold plate recovery system. We have couple rectifiers in our disposal: one that is 10 Volt 80 Amp second is 4 Volts 5-30 Amp, and the third is 6 Volt 10 Amp. This is used for copper plate. I don't want to use sodium cyanide, too dangerous. Is the any other chemical that I can use for the solution to strip gold from copper and stainless steel? What rectifier will perform the best to strip gold from other metals? The left out metal materials are going to be properly disposed, and only gold recovered and kept. Any help will be appreciated. Paul.
Paul PriHobby, Student - Erie, Pennsylvania
March 3, 2008
Q. Can anyone help....? I have a pretty rare military cap badge that someone has gold plated for display! The base metal is bronze and my local jeweler tells me that if he tries to un-gold plate it electrically in an acid solution, it will eat the bronze away and ruin his £200 solution and my badge. I have tried to gently rub it off but it's impossible.... any suggestions?
Howard Smith- Cardiff, Wales, G. Britain
March 4, 2008A. Hi, Howard. Please carefully reread David Vinson's reply -- I think it's what you are looking for. You need to find a shop who will mechanically polish the gold off. Good luck.
Ted Mooney, P.E.
finishing.com
Brick, New Jersey
April 10, 2008A. 1000 ml H2SO4 in 2000 ml Pyrex casserole dish with approx. 1/4 teaspoon of glycerine well mixed into the H2SO4. Submerge a lead bar or rod in the dish with enough of the metal sticking out to connect the negative (-) lead. Obtain a variable power supply (10 AMPS MAX) @6-12 volts -- a battery charger [linked by editor to product info at Amazon] works great!). Connect the negative lead to the lead electrode. Connect the positive (+) lead to a cable with STAINLESS STEEL ALLIGATOR CLIP. Attach the item you want stripped to the clip, turn on power supply and lower the piece you want stripped into the acid/glycerol solution. PRESTO--CHANGO! The black residue is approx. 95%+ pure gold. You will need to dissolve and purify product with Aqua Regia or HCl and regular Clorox Bleach (halide leaching). This is simple, safer than HNO3 fumes. I have been using this for years with great success. Good Luck!
Les M. Barnes, LAC
- Carolina Beach, North Carolina
August 23, 2008
Q. Hi I just read your letter and can you go in to more detail and explain the chemicals you are talking about on the halide leaching , bleach etc , I have the black mud and need to get back to gold. thanks Mike
Mike Giannio- Millville, New Jersey
September 15, 2008
Q. Hello
I've got a gold plated i.d. bracelet that I've had for twenty years. half of the gold plating on the bracelet has worn to leave it silver and gold. what can I use to remove all the gold to turn it completely to silver?
thanks
ronnie
- Christchurch, New Zealand
November 28, 2008
Q. I have about 20 pounds of 1/4 inch x 1 inch 360 brass rods that are gold plated. How do I recover the gold?
John UrspruchMusical instrument repair tech. - Brick, New Jersey
January 11, 2009A. You can it resolve in AR and recover it with sodium disulfate that is known as recovery chemicals and wash it with DI water
David Babu
- Kerala, India
October 2, 2009
Q. I have some aluminum chain that is gold plated and I would like to remove the plating. Can it be done without damaging the chain and what should I use?
Alexander Gray- Bedford, Ohio
March 7, 2010
Q. I have 8 sets of 24k gold plated silverware and would like to remove and recover the gold but I need it step by step so I don't bugger any of it up.
Pookie Bazemore- Norman, Oklahoma
March 2010A. Hi, Alexander; hi, Pookie. There are things that a competent person can learn how to do from written instructions, like painting a wall or baking a pre-mixed cake. And there are things that a person won't learn to do from step by step instructions, but only from practice with supervision, like rebounding a basketball well or piloting a jetliner. You can search the internet forever but you will never find step-by-step instructions for those things.
As you are discovering on this page, people do tell you that mechanically polishing the gold off may be a better way to go than trying to dissolve it, but they can't give step-by-step instructions for recovering the gold and not damaging the chain or flatware because it's an acquired skill. You can take it to a plating shop for removal of the gold, but almost surely this will cost money, not pay money, because the value of the gold is minimal compared to the effort in removing it. Good luck.
Regards,
Ted Mooney, P.E.
finishing.com
Brick, New Jersey
January 4, 2011
Q. How can a person recover the gold from 22 ct. plated stamps?
Hobbyist - Coos Bay, Oregon USA
August 3, 2011
Q. Hello there!
I have just done my first gold plating, a large bracelet, brass 15.5 x 6.5 cm, plated with 18k ready made mixture. I used a magnetic mixer and rectifier, my problem is the color came out not nice and I want to strip it and redo the piece. I was reading the thread but got more questions: the sulfuric acid/glycol mixture suggested by Les Barnes seem easy enough, I want to know: do I have to heat up the mixture if so, what's will be the temperature? Can I use the titanium sheet instead of the the lead rod. Please explain as I have no clue as to what I am doing.
- Hong Kong
August 18, 2011
Q. I have about 25 pound of aluminum 'parts' that are electroplated in gold. I understand that this gold (although pure) is probably VERY thin (microns). Is there any significant value in stripping and collecting this material through a precious metals vendor? I would REALLY appreciate and answer, thanks for all the good work you do on this site.
Jeff Constantinescrap dealer - Mission Viejo, California
August 19, 2011
A. Thanks, Jeff.
You are right that it is likely that the gold is very thin. I would saw one of the items in half and try to estimate the thickness of the gold with a jeweler's loupe or a microscope. Until you have some idea of the thickness, it's impossible to estimate the amount of gold that is there. Once you do know the thickness, it's relatively easy. If it's thousands of dollars worth of gold, it's worth it despite any difficulties. If it's $35 worth of gold, it's not going to be worth the cost of recovery.
Regards,
Ted Mooney, P.E.
finishing.com
Brick, New Jersey
October 5, 2011
Q. How do I strip the gold off the Indy Car where I can sell it, I bought the indy car about 15 years ago it is of the 1998 GRAND PRIX OF Houston
Robert AcevedoI am a home owner - Angleton, texas US
October 6, 2011
A. Hi, Robert.
These cars are, as you know, collectibles. I think you'll get far more from selling it as is than from stripping it. But if you insist, then start by cutting the car in half and estimating the gold thickness with a microscope. You'll want to know how much gold is there (I suspect it's not much). I've heard of people scraping the gold off the contact fingers of printed circuit boards, and that may be the best way for you to get the gold off. Good luck.
Regards,
Ted Mooney, P.E.
finishing.com
Brick, New Jersey
January 26, 2012
Q. Retired vet needs some answers. I would like to know if I can take and process it all back to gold. Is it diff. from the rest of this thing I have been buying this stuff for years.
Mike Andersonlooking to help keep the earth - Des Moines, Iowa