Need your help in understanding Aqua Regia

[aayushk]

First off I would like to apologize for posting this new topic in Rocky Talky, I know this post does not belong here but wasnt sure where it does belong. I figure if I post it in the most active section I could get some much needed guidance.

I have been doing a lot of reading online into understanding how Aqua Regia is used to dissolve gold. I understand the part where we have to use a 1:3 ratio of nitric acid to concentrated hydrochloric acid, which chemically forms "aqua regia". I also understand the dangers of the toxic fumes and have created an area where i can perform this task safely. However all articles mentioned online pertain to using this for circuit boards and computer processors so I''m somewhat concerned with how the procedure will work.

I am interested in dissolving about 200 rings. They are all 14K white and yellow gold, and have channel set diamonds. The reason I would like to dissolve them is to recover the diamonds with little to no breakage and extract the gold to reuse. From what I have read the process is as follows:

1. Pour nitric acid in glass beaker
2. Submerge the rings in the beaker
3. Pour concentrated hydrochloric acid into beaker
4. Wait until diamonds settle on the bottom and gold becomes liquid
5. Separate liquid from diamonds
6. Clean diamonds with sodium bicarbonate (to neutralize aqua regia)
7. Then clean diamonds in isopropyl alcohol - diamonds are recovered safely and reusable.

8. ........WHAT DO I DO WITH THE LIQUID GOLD? How do I solidify it, or what is the next step?

Once again this is what I have understood from reading, but if you have first hand experience with this procedure and if you could guide me in the right direction I would really appreciate it.

I want to thank everyone for helping me out in advance!

 

[Fly Girl]

I have a degree in chemistry, and your proposal is a very dangerous way to extract the diamonds. Please don''t go this route. I''d much prefer to see you do the diamond extraction using mechanical, rather than chemical, methods.

 

[partgypsy]

I''m not a chemist and hopefully someone who is more knowledgeable will pip up but I agree that seems like an awfully involved dangerous and "toxic" way of getting diamonds out a ring and (possibly) recovering the gold.

I would either investigate selling the rings as is; you would get the most money as a ring than as components. Unless the diamonds are extremely high quality most probably the gold is worth more than the diamonds on the resale market. I think you need to go to a jeweler/pawn shop, etc and get more information what the relative worth of the rings are, see if anyone willing to buy the rings as is or just for the gold, and if it is just for the gold they will remove the stones mechanically.

 

[Richard Sherwood]

Can I take out an insurance policy on ya?

 

[denverappraiser]

Why not just use a refiner that offers this service and is prepared to do it in a professional way? Most will do it. The few dollars you save in terms of fees are going to be eaten up quickly when you look into the cost of skin grafts.

Neil Beaty
GG(GIA) ICGA(AGS) NAJA
Professional Appraisals in Denver

 

[aayushk]

Fly Girl = I understand that the procedure is dangerous, however considering the circumstances mechanical labor would be extremely expensive and the diamond breakage would be way too high. That is why I''m investigating this method, its actually a common process amongst refiners and I''m just entertaining the idea that I could do it on my own. If I don''t feel safe enough to do it on my own I wont try, I will just send it to the refiners.

Part Gypsy = I wish I could sell the rings as is, they are nice and I know they would sell. But unfortunately these rings are lasered with a logo of my customers company, whom did not pay for the goods so hence I cannot sell merchandise with their name on it. We are the manufacturers of the rings! The diamonds are G-H, SI1 and there are about 16 diamonds in each ring, rounds and baguettes. If we went mechanical you can pretty much say goodbye to all the baguettes. Pretty much already lost money on the deal, but trying to minimize the damage.

Richard = very funny! LOL. I wouldn''t be surprised if my eyebrows end up missing by next week LOL. I wont be trying anything unless I''m completely aware of all the dangers, and consider it safe for us to do ourselves.

Denver Appraiser = The last time we did it through refiners based here locally the diamonds "mysteriously disappeared". I have tried a few refiner''s and have come the realization that they aren''t the most honest people.

I WOULD LIKE TO LET YOU GUYS KNOW THAT I WON''T BE DOING THIS IF IT BECOMES A HIGH RISK SITUATION. WITH THE PROPER EQUIPMENT AND PROPER STAGING GROUNDS THIS PROCESS HAS BEEN PROVEN TO BE EFFECTIVE AND HARMLESS. AND WE WILL HAVE SODIUM BICARBONATE ON SITE TO NEUTRALIZE THE CHEMICAL REACTION IF ANYTHING DOES NOT GO AS PLANNED...

 

[denverappraiser]

There are, of course, problems in every industry with less than honest people and refiners are no exception but I think it’s a mistake to disparage the entire industry based on a few members. The same criticism apply to jewelry manufacturers and jewelers after all. The key is to pick the right people. I agree that it's possible to do this safely, and it's obviously possible to learn the skill if you work at it but it doesn't strike me as the sort of thing to enter into lightly or for someone who only wants to do it a few times.

I’ve seen good luck with these guys in Dallas at this service.
http://www.ntrmetals.com/

http://www.preciousmetalswest.com/ in LA is also well regarded for this.

Neil Beaty
GG(GIA) ICGA(AGS) NAJA
Professional Appraisals in Denver

 

[HopeDream]

Hi Aayushk,

PLEASE PLEASE DON''T TRY TO DO CHEMISTRY BASED ON A WIKIPEDIA ENTRY!!!!!!

If you need chemistry done contact a chemist!

I recommend contacting a local university to see if any of the cash-strapped graduate students in the chemistry department would do it for you on a contract basis.
It''s summer now, so many of the school labs are underused and have space for this kind of project.
They have the apropriate equipment and could probably get the job done SAFELY for the cost of the chemicals plus a reasonable fee for their time and expertise.

Academics are often cash strapped and may be willing to take on contract work like this - plus they probably don''t have any contacts in the jewellery industry.

Researchers are used to dealing with small quantities of very valuable chemicals
Just count the number of diamonds before you melt the rings and make sure that number comes back to you.

I mention this because my high school chemistry teacher would occasionaly refine silver this way as a favour to a local jeweller in my home town.

Good luck!

HD