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

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


on eBay or

AbeBooks

or Amazon

(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.

Success,
Harry

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

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 affil links] .

Regards

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!

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

A. TRY KCN, BE VERY CAREFUL - -POISONOUS -- CHECK MSDS FIRST.

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!

! 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!

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.

A. Testing of GPC is very easy. Take 10 ml cons. sulfuric acid in a 50 ml beaker [beakers on eBay or Amazon [affil links] . 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.

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!

Regards,

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,