How much aqua regia per oz of plated scrap jewelry?

[kadriver]

I am getting ready to refine my first batch to 999 from some gold plated jewelry. I also have some gold plated silverware with base metal that looks like cast iron. I will do the plated jewelry first by itself. Then some of the gold plated silverware.

I will be using an older heavy pyrex coffee pot with a glass lid. I have cut the gold plated jewelry up into small 1/8 to 1/4 inch pieces. There is about 300 grams of material.

I have several questions for some of you more experieced refiners out there.

1) how much aqua regia should I use for this batch of 300 grams of gold plated material? Can I just add the AR and cook it like you would with SOLID scrap jewelry? (SOLID meaning 10k, 14k, that is not plated).

2) OR, should I add nitric acid alone first to dissolve all the base metal? Then neutralize with urea, filter, wash and rinse. Then dissolve the gold left over with AR and proceed from there?

Hope I have not been too ambiguous.
Thank You! - KLS

 

[nickvc]

I suggest you read Hoke before you even start this!
In plated jewellery your going to find all sorts of metals that will cause real problems including tin and lead, these will give you severe headaches trying to recover your values and you will be lucky to get 90% Au let alone 999.
Hoke is available as a free download here on the forum and I really think you should study it before you start your experiment so that your equipped to sort out these problems or at least be aware of potential problems and solutions to them.
This isn't a dig at you but I hope a timely warning so you avoid problems.
Nick.

 

[goldenchild]

The material you have in that jar actually looks like it could be gold filled but for the purposes of your question I will treat it as plated scrap. First let me tell you that 300 grams of plated material wont yeild much gold. So little in fact that I would not recommend going to AR first as you might lose the gold in the shuffle.

I also wouldnt use straight nitric as it would be a waste for such a small amount of gold. I would suggest you build a stripping cell and use that. Wait until you've stripped enough material to make it worth harvesting from your cell. Do you plan on plated material being your primary source of gold?

Lastly, if you're sure some of the material you have is gold over silver, you should use straight nitric on it . This way you will dissolve the silver and leave behind the gold plating for seperate processing. As nickvc suggested, read Hoke before even attempting this as the questions you asked are pretty basic things in this great hobby we call refining

 

[kadriver]

Thank you. I don't want to waste my chemicals. I will read Hoke, where can I find it and what is it. Thanks for your input.

I plan on refining mostly SOLID scrap 10k 14k 18k. The plated jewelry is some I have been accumulating and was going to try the process on this.

I am not going to do anything until I have studied all I can.

Using a stripping cell sounds interesting, I would like more information on that process.

Thanks again and don't worry, I take critical input well.
- KLS

 

[nickvc]

Use the search function for any information you want.
C.M.Hoke is tagged onto the signature line of several members and moderators,it really is the bible for refining ,it's old and written by a woman but gives you the basics in an easily understandable way even I can understand it :lol:

 

[goldsilverpro]

Plated costume jewelry is almost worthless unless you have a lot of it. It is usually worth from 5 to 10 cents per square inch of gold plated area. There is some that can be worth about 20 times more, but it is usually marked HGE, Karatclad, etc.

In any case, you don't want to use aqua regia to dissolve everything. You'll end up with so much metals solution that the small amount of gold can easily get get lost in the shuffle. You're much better off first dissolving only the base metals and then removing the solution and dissolving the gold residue in aqua regia or HCl/bleach. Lazersteve has several short videos on his website that explain how to dissolve the base metals using inexpensive muriatic acid and hydrogen peroxide. He also sells an excellent, inexpensive, more complete DVD on the subject, I believe. You can also use nitric acid to dissolve only the base metals but it's a lot more expensive.

http://goldrecovery.us/

 

[goldenchild]

Thank you. I don't want to waste my chemicals. I will read Hoke, where can I find it and what is it. Thanks for your input.

I plan on refining mostly SOLID scrap 10k 14k 18k. The plated jewelry is some I have been accumulating and was going to try the process on this.

I am not going to do anything until I have studied all I can.

Using a stripping cell sounds interesting, I would like more information on that process.

Thanks again and don't worry, I take critical input well.
- KLS

I didnt mean to be hypercritical but just informative. You will find however, that we will gladly give you a kick in the @$$ if we feel you are going in the wrong direction. Especially when safety is an issue. Its for the good of you and anyone else reading these posts. Welcome to the forum.

You'll end up with so much metals solution that the small amount of gold can easily get get lost in the shuffle.

I said the same thing. What exactly is the shuffle? :lol:

 

[goldsilverpro]

I said the same thing. What exactly is the shuffle?

Sorry, goldenchild, I really didn't see that you had said the same thing before I posted, Great minds work together, I guess.

 

[kadriver]

Hello: Thanks to you people, I think I just saved myself some grief and some money. I have put off the idea of trying to refine this jar of plated scrap jewelry. I will save it for later on down the line after i have some experience and more knowlege - I found the Hoke book at my public library.

This is a wonderful forum - keep it up - WOW!
KLS

 

[butcher]

kadriver, that is a wise decision, taking time to learn will save you money, time and trouble, and possibly your health. the gold will still be there and you will have an education of how to get it.

 

[patnor1011]

Hokes book is in my signature for download. You will not loose anything even purchasing hard copy as this book is a must have for anybody who want to refine gold.

 

[Texas]

C.M.Hoke is tagged onto the signature line of several members and moderators,it really is the bible for refining ,it's old and written by a woman but gives you the basics in an easily understandable way even I can understand it :lol:



sorry my question, not wanting to sound sexist, but Hoke was a woman?
oh! the reason is book is so simple and easy to understand ... Thanks for your legacy Hoke ... Thanks for your legacy Hoke

 

[Palladium]

sorry my question, not wanting to sound sexist, but Hoke was a woman?

Yes !

 

[Palladium]

sorry my question, not wanting to sound sexist, but Hoke was a woman?

Yes !

I've spent the last hour or two researching who she is and where she came from, even her kin folks. Does anyone know what her whole name is? What year she was born? Guess what famous person she was related to who invented a torch? I'm trying to chase down the family tree and see how interesting this story can get. 8)

 

[Harold_V]

It is rather interesting that Hoke was a woman, but, aside from her suggestion to use gasoline for incineration, she didn't miss a lick in that book. What she teaches will serve anyone perfectly well, assuming their interest is in ending up with fine gold. She doesn't treat silver with much interest, due in part to its relatively low value at the time, but even silver should be addressed with respect, especially if it is used for inquartation. When it is, it becomes the carrier of platinum and palladium, both of which are found in dental gold, and to a lesser degree, in jewelry.

Where her book shines brightest is in teaching how to test. A person that can't test is subject to making poor purchases and likely to discard values unnecessarily.

I admonish readers to read Hoke, in spite of how much they may think they know. Read her book until it makes sense. It will serve you better than any one other source of information. As you progress in your refining skills, it will become apparent just how valuable she was to the small time refiner. Remember, it was illegal for residents of the US to refine without a federal license, until January of 1975------so there was little incentive for anyone to publish on the subject. I expect it was not a big profit maker for her. Her reward, like that of most artists, comes well after her passing.

I note the post above mine----her father was the man after which the Hoke torch was named. He was a well known authority on platinum in his day. I know little more.

If memory serves, the C in her name stands for Comfort. Strange name.

I stand corrected on her name, which is Calm. Thanks, GSP & jimdoc.

There is precious little information available on the Hoke family.

Harold

 

[jimdoc]

This is what i found;

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=67&t=7947&p=74473&hilit=hoke#p74473

Calm Morrison Hoke

 

[goldsilverpro]

Her name is Calm Morrison Hoke.

http://books.google.com/books?id=mpxTAAAAMAAJ&q=calm+morrison+hoke&dq=calm+morrison+hoke&hl=en&ei=p8LuTOGnOMP_lgfNjdGsDA&sa=X&oi=book_result&ct=result&resnum=1&ved=0CCUQ6AEwAA

https://encrypted.google.com/search?hl=en&lr=&tbo=1&tbs=bks%3A1%2Clr%3Aall&q=%22calm+morrison+hoke%22&aq=f&aqi=&aql=&oq=&gs_rfai=

 

[Palladium]

http://genforum.genealogy.com/hoke/messages/682.html

http://www.freepatentsonline.com/1438999.pdf

http://catalog.loc.gov/cgi-bin/Pwebrecon.cgi?DB=local&Search_Arg=c+m+hoke&Search_Code=GKEY%5E*&CNT=100&hist=1&type=quick

http://cabinetcardgallery.wordpress.com/category/photographer-morrison/

 

[goldsilverpro]

Someone recently gave a link with a photo of her. I think it was in Google Books.

 

[jimdoc]

http://books.google.com/books?id=9VJIAAAAYAAJ&pg=PA53&dq=cm+hoke&hl=en&ei=0OOgTO2-FoL_8AbKrcSDAQ&sa=X&oi=book_result&ct=result&resnum=9&ved=0CFYQ6AEwCA#v=onepage&q=cm%20hoke&f=false