What do I do next

[donnybrook]

Forum Members,I have just recovered some gold using the SWAN Leach and also some more using a Halide Leach. I precipitated the metals with SMB, then boiled these in caustic or Lye which converted them to a dark oxide. I then roasted these in a cast iron Camp Oven over my furnace which turned these into a yellow mustard powder.  Normally I would recover on a table ,smelt and granulate,undertake a dissolution and drop clean gold with SMB. Clean this with Ammonia,Nitric and then Hydrchloric acid. A further clean with ammonia and a boil in water which lumps the powder together. Can this yellow mustard brown powder be redissolved and again dropped using SMB or do I have to smelt this first. Both Manuel and Carl on the Forum have been a fantastic help.

How would other members approach this at this point?It is a great Web Site.DonnybrookAustralia

 

[butcher]

what is this swan leach? have not heard of that.

sounds as you have roasted,
sulfides need greater than 700 degrees and some time and air exposure, an hour or untill your sure get no more SO2 from them, driving acids out and oxidizing the metals can improve your recovery
if these powders are failrly clean, I would use dilute nitric wash, caution powdered metals get Very reactive
then aqua regia, dont forget to eliminate the nitric before trying to precipitate the gold, alot of times a second disolving in a aqua regia is needed for purity.

 

[donnybrook]

Butcher,
The SWAN Leach is the Salt Water and Nitric Leach which you would be more familiar with. It is very effective (you can add a small amount of Iodine) After recovery of your concentrates you grind, roast to red heat, rinse with water then clean with mild acid. I then follow with a further grind and flush the concentrates several times. Dry again and add the SWAN Leach (which is aggressive on its own without Iodine) and agitate. I am working on two different concentrates from different areas and the response to the leach varies with both. It is also referred to by Charles Butler as the "Walter Lashley Salt Water and Nitric Acid Leach". You use Urea for the Nitric and then precipitate. Because it is a different process to what I used previously I thought I would ask on how you or others would clean up or re precipitate. My buyer just buys the powder after AR and then precipitating with SMB which produces a very clean heavy precipitate requiring minimal cleaning. Let you know how I go.
Thank you for your advice.
Donnybrook.

 

[Platdigger]

Over here we call it SSN.
Saturated saline (or salt water) and nitric.

 

[butcher]

after refining or rerefining, look into evaporation instead of urea, and using added gold to eliminate nitric, Harold's wash works great, similar to what you have been doing.
with a little time spent reseaching the forum you should be able to refine your gold to a very decent purity, saving you refining cost, there is more too it, than we can post in one or two reply's, but all the information is here for you. sounds as though you know most of the basic's which will help.

 

[donnybrook]

My thanks to Butcher and Platdigger for the information. This is a great Forum with so much information for many like me who like to chase the PM's. There have been references to a book by Hoak and also Bugbee. The last book by Bugbee was supposed to be on smelting or furnacing metals but he gives so much added information. I have a book which is over 100 years old. It would probably only be of interest to those who are processing alluvials or mines materials but it does provide a great deal of information on Wet Assays for all metals known at the time. Two other Forum members Cad and Manuel have given me so much support. I don't know of any other Aussies (there are some registered on the Forum) that are interested in the many recovery methods used over there.

It has been because I have used some of the leaches on the forum for the first time that I have been uncertain about procedures. I am still not sure how to recover the Iodine used for a leach. It is expensive here. I pay approximately $200-00 (au) a gallon for it. It is in the solutions which are clear and there must be a way to bring this back?The late Ken Williams would always get back to you with an email. I only knew after joining the Forum that he had passed on and it saddened me as he is a great loss to us small scale miners and precious metals recoverers.

I will post something back up on the Forum after I produce the yellow metals. I have basically used the SWAN Leach or SALINE and Nitric (SSN) procedure on one lot and Iodine on another, both being the same weight. Nothing really exact or scientific about that but I'm interested to see which leach works best.

Again my thanks.

Donnybrook
Australia

 

[manorman]

I have had some luck witn Iodine leach recovery, i think use a differant recovery methed then you do,
i leach my ore for two days, then add lye to drop my PMs, i then add a excess of bleach to reduce my iodine to an elemental state,
i remove about ninty five precent of the clear liquid, i then add citric acid to bring down the PH, then when im ready to use again i add bleach a drop at a time until the solution turns red.
I am sure the citric acid( i used vinager) is not the best acid to use i just have it at the house so i tried it and it worked so far,
you might try with a small batch to see if you have simular results, belive me im no expert but so far its worked.
Mike

 

[Platdigger]

Hi Mike,
Welcome to the forum.
Mind if I ask the type of ore this worked on?
I mean like, placer deposit or, hard rock?
Thanks, Randy

 

[manorman]

It's placer deposits, i dont not process large amounts only 10 to 15 pounds at a time.
once i drop with lye, i decant the values then add the excess of bleach that leaves yellow powder after a short time i then decant most of liqued And then add the vinager( about 3 or 4 times the volume of what remained afer i decanted) covered in air tight container, afer a few days it starts to turn a pale red, then before i use i add drops of Bleach and it turns a much darker red, if it does not turn a dark enough red i add some fresh 7 percent iodine tincure ( about 2 ounces per gallon of recoverd liquid), than add distiled water and add my dirt.
the have some good PDF files of patents on the fourm that make for interesting reading just type iodine leach i the search bar.
i heard some say you can drop the gold and silver with SMB, and your leach will be good many times without having to use the bleach to
drop your elemental iodine, they say it works untill the copper and iron bulid up, not sure if it works i will try it someday,
Mike

 

[donnybrook]

MIke and Randy,
Thanks for your input and information on iodine and its recovery. It now makes a bit more sense. Still having trouble with a flux. The charge is very reactive and I wonder whether I am possibly co precipitating something with a higher temperature if that is possible. I usually only use borax after drying and cleaning the powder (if I drop the PM's using SMB) . Is there a particular flux that should be used. Perhaps you could advise whats best to use with his type of precipitate. Very much appreciated.

Don

 

[EVO-AU]

Manorman:

I just came across a post of yours dated Sept of this year about using vinegar for dropping pH. I have a book written in the 15th century about how they used vinegar and water for washing the gold powder instead of HCL and water. Most interesting. Phill

 

[EVO-AU]

Donnybrook:

I see you are from Australia, are you by any chance a shuffler ? Phill