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What is gold potassium cyanide, where is it used, how to prepare, how much?

Q. I am producing gold dicyanoaurate (gold potassium cyanide, GPC), KAuCN2, by electrolysis, but when testing it at an acidic pH, it presents turbidity from a pH of 3.9.


The bath in which we use it can sometimes reach 3.0, so we must guarantee that it remains stable until that pH. Do you have any idea what this is due to?

Daniel Barrera
- doral florida
April 12, 2024

⇩ Related postings, oldest first ⇩

Q. 1). what are the different ratio of gold in g.p.c?

2). books related on gold plating for electronic industry, other industry and give me a website address for related universities?

thanking you

kiran Y [last name deleted for privacy by Editor]
gujrat India

"Gold Plating Technology"
by Reid & Goldie
(hard to find & expensive; if you
see a copy cheap, act fast)

on AbeBooks

or eBay or


(affil links)

A. 1. Potassium gold cyanide = KAuCN2, containing 68.2% by weight of Gold.

2. "Gold Plating Technology" ⇨
I guess it's sold by the Institute of Metal Finishing, probably NASF has it too.


Harry van der Zanden
Harry van der Zanden
- Budapest, Hungary

Q. I want to know about shelf-life of potassium gold cyanide in electroplating industry. How to organize some potassium gold cyanide if it's kept in the wrong condition and is it devalued when it oxidised by air. Please answer this question in the in a general way. Thanks a lot.

Soraya v [last name deleted for privacy by Editor]
- Thailand

A. Good quality GPC is an extremely stable complex and will not oxidise in air easily.

de-wet Combrink
- South Africa

What is Gold Potassium Cyanide Used For?

Q. Can anyone please tell me what gold potassium cyanide is used for. I know it's used for electrogilding, but what is electrogilding? Is it used for anything else?


Lisa [name deleted due to age of posting]
- Toronto

A. Lisa,

Potassium gold cyanide is the chemical used to provide the gold in solution for gold plating. Simply speaking the PGC is dissolved in a solution of potassium cyanide, water and perhaps some potassium hydroxide along with salts (often proprietary products) to provide conductivity to the solution.

The gold is deposited onto the work by making the work the cathodic (-) and the metal tank (or other separate anodes) anodic (+) with a low voltage high current direct current power supply.

The gold that is dissolved in the solution is deposited by the passage of the electric current onto the work.

This is an abbreviated simple example and if you want more info search your local technical library as there are many books written. Try Gold Plating Technology by Reid & Goldie [on AbeBooks or Amazon (adv.)] .


bob lynch
Bob Lynch
plating company - Sydney, Australia

Q. Lisa has asked something I really would like to know but you seemed to have forgotten the question. She asked what was electrogilding. Please answer this question. I really would like to know.

Samanda S.
- Toronto, Ontario, Canada

A. Samanda, please start by thanking this volunteer who is trying help you, rather than criticizing him.

But Bob did answer: "[Electrogilding is a process wherein] the gold is deposited onto the work by making the work the cathodic (-) and the metal tank (or other separate anodes) anodic (+) with a low voltage high current direct current power supply ... The gold that is dissolved in the solution is deposited by the passage of the electric current onto the work."

Please explain your particular situation rather than posting in the abstract. If I were to ask "what is sugar?", you'd see why: sugar is one thing to a med student, another to a ping pong player, another to a biologist, another to a dietician, another to a jazz musician ... okay, sugar?

Where and under what circumstances did you hear the term "electrogilding" that motivates your question? It probably simply means "electroplating with gold", but we can probably help further if you can please put it into context for us. Thanks!

Ted Mooney,
Ted Mooney, P.E.
Striving to live Aloha - Pine Beach, New Jersey

A. Lisa,
Electrogilding is deposition of gold on electric conductor (cathode) in electrolytic cell.

Prof. Pavel CIBIN
University of Montenegro - Podgorica, Serbia and Montenegro (former Yugoslavia)

Q. I am currently conducting a study on the Potassium Gold Cyanide PGC Market in United States. I am looking for the price for Gold Cyanide and how it is linked to the gold official price : how much would a consumer pay for the gold and what can be the range of processing charges ?

I am also looking for the important PGC producers (for example Technic, Metalor, LeaRonald, Engelhard, Johnson Matthey : did I forget an important one? -- and the important retailers that do not manufacture PGC but only sell it.

If you can help me it will be very useful for my study.


Redouane Abbas
- Paris

Preparing gold potassium cyanide

Q. Hello,

I am new gold plater can any body help me to change my old procedure to prepare gold potassium cyanide? My procedure:
aqua regia+gold=AuCl3
AuCl3+NH4OH=gold fulminating
gold fulminating+KCN = GPC.

Please answer me.


Haythem M Jweid
- Mosrata, Libya

How to dissolve gold potassium cyanide for coating purpose

Gold potassium cyanide solubility, i.e., in which solvent is Gold potassium cyanide soluble? I have a powder form of Gold potassium cyanide. How to dissolve it so that it can be used for coating.

student - CHENNAI, Tamil Nadu, India


Cair Shishani
Khair Shishani
aircraft maintenance - Al Ain, UAE

[editor appended this entry to this thread which already addresses it in lieu of spawning a duplicative thread]

Q. Please respond immediately. I have a question: will gold potassium cyanide dissolve in water?

Jenn Mcnerney
- Santa Rosa, California

A. Hi Jenn. Please see answer directly above.
Please provide full context rather than a flash card quiz because you're speaking of very dangerous chemicals & very dangerous situations; no one can properly warn about these potential dangers if we don't know whether you're a high school kid mixing stuff on the kitchen table or a post doctorate working under a fume hood with cyanide detectors and a wet washing system to guard against possible fulminate explosions. Thanks!

Ted Mooney,
Ted Mooney, P.E.
Striving to live Aloha - Pine Beach, New Jersey

Gold potassium cyanide for a plating project

I am in the middle of gathering supplies for a plating research project. The project requires the use of potassium gold cyanide, and I wanted to know what difference there might be if I were to use Gold Potassium Cyanide instead. If any one can help me, I would appreciate it.

Dylan Leischow
student - Germantown, Maryland, USA

Might there be a typo in your question, Dylan? I believe that PGC and GPC are one and the same.

Without knowing what your project is, I hesitate to say this, but it should be said for the benefit of most readers: don't make your own plating bath from basic chemicals, buy a proprietary plating process.

Ted Mooney,
Ted Mooney, P.E.
Striving to live Aloha - Pine Beach, New Jersey

Q. I want to know the manufacturing process of potassium cyanide.

Jignesh V [last name deleted for privacy by Editor]
student - Bharuch Gujarat India

! Hi Jignesh, please try to focus on the manufacturing of less hazardous materials for your school project! After you're in industry and have received several weeks of highly specialized hands-on hazmat and safety training, have been fitted with proper personal protection equipment, in a lab equipped with cyanide detectors and antidotes, then you will learn how to manufacture this exceptionally hazardous material. The tiniest amount accidentally ingested or inhaled will kill you and quite possibly your would-be rescuers, so we don't want to encourage experimentation!

sidebar I'm sure some readers are saying to themselves: "the student only wants to know how, he didn't say he wants to do it: don't be a control freak". But the internet is a gigantic one-room schoolhouse, and if Jignesh doesn't attempt it, this page will be read by thousands of people, and the next reader might; it's not possible to attach detailed safety instructions -- hands-on training must be done. Sorry.
Ted Mooney,
Ted Mooney, P.E.
Striving to live Aloha - Pine Beach, New Jersey

A. Testing of GPC is very easy. Take 10 ml cons. sulfuric acid in a 50 ml beaker [beakers on eBay or Amazon (adv.)]. Pour 1 gm of GPC sample into it. Cover it with a watchglass. Boil it in open atmosphere for approximate 15 minutes so that the hazardous cyanogen gas can get away. Initially the solution will become brown and after completion of reaction, solution will become colourless and you will find a ball of powdered gold in bottom of the beaker. Let it be cool because the boiling point of sulfuric acid is more then 200 °C. After cooling, decant the supernatant liquor carefully and wash the residual gold thoroughly. Then dry it and weigh. It will give you the true percentage of Gold present in the sample.

Sandeep Garg
jeweller - Ghaziabad, U.P., INDIA
June 8, 2008

Q. Is Gold Potassium Cyanide as toxic as Potassium Cyanide?
Thank you,

M. R. Fino
- Boston, Massachusetts, USA
March 21, 2009

A. Hi, M.R. No, gold potassium cyanide is not as dangerous or as toxic as potassium cyanide ... but gunpowder is not as dangerous as TNT. Please tell us what you are getting at, because GPC remains plenty dangerous, and responses offered in an abstract way may cause people to understate the dangers. Thanks!


Ted Mooney,
Ted Mooney, P.E.
Striving to live Aloha - Pine Beach, New Jersey

Q. We have a small scale firm of fashion Jewelry. We are using micro plating technology for gold plating of jewelry so we purchase Gold Potassium Cyanide (G.P.C) salt packets from local vendors for gold plating purposes regularly. But these salt packets do not have standard seals for quality. So please suggest how to know the quality of the product -- and is there any organisation which will provide standards seals on these packets?

Pavan Kumar
- Andhrapradesh, India
April 16, 2012

Q. When I'm preparing GPC, what kind of ventilation system is required and how is it arranged? It should be taken a laboratory full uniform necessary. I want to prepare that compound. Any suggestion?

mohammad anwar
almas chemicals - jalgaon, Maharashtra, India
May 7, 2012

PGC acid bath test

Q. A client is performing an acid bath (pH 3.0) with our PGC to test the PGC for stability to see if gold precipitates . My gold lot would be 99.97 in purity. Could there be a problem in this test? Thank you for your valuable help !

John davids
- Ontario canada
February 17, 2015

Q. Sir, any other process for gpc? If we add gold precipitate into potassium cyanide solution, it makes gold potassium cyanide & potassium chloride. How do we separate it?

Amol Jain
gold plating - shirpur maharastra indiashree
July 14, 2015

Hi Amol. Please search the site with the phrase "How to make GPC". There are several very detailed threads on the subject here including thread 2236.

We continue to reinforce the point that manufacture of potassium gold cyanide is only for experienced chemists who have received hands-on haz-mat training and specific study of the dangers of cyanide :-(

Luck and Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
Striving to live Aloha - Pine Beach, New Jersey

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