Cleaning gold

chopppacalamari wrote:This is how I've set up my acid. The acid is surrounded by a water/bicarb soda solution to neutralise any acid that may spill if it is bumped and to neutralise the acid on and in my nugget when I want to take it out. So long as there's still bicarb visible on the bottom of the bowl I know the solution is at its maximum strength.

Looks like something in a Dental Surgery Choppa.

Mick,

PS, Is that pink stuff MRS Marsh would soak the chalk in on some Colgate add years ago?

hi
you can get septone ali brite from Blackwoods in 5 lt , part nº 0502 2566 and 20lt ,part nº 0044 4125. i was quoted a price of $91.80 for the 20 lt but that includes what ever discount the company i work for is on.
dave

You can purchase Alibrite and all other Septone products from BCF camping stores.

Hey ya! Tis off topic a smidge but may be useful. Cleaning gold not necessarily extends to nuggets. I was quite ponderous last year when my alluvial fines turned silver in the trip bottle overnight. Hmmm I mused, what made my gold turn silver. All i did was stumble around the river bed whilst the bottle was in my pocket, then silver thus did appear. Somewhat perplexed i then mused. Turns out the answer was quicksilver. A recent flood has thrown the mercury up and it was stuck to the larger bits I got. This then spread to all other bits. After musing of such occurance i got some nitric acid from chem world which cleaned them up a treat. my silver turned backed to gold once more. i wonder then if the nitric acid dissolves the mercury can this acid be a similar equivelant to the alibrite to dissolve the iron, or is it just one of those jewellers tools. Whatever!

Or ya cudda just warmed it up well above room temp and the mercury woulda bin gone. CAUTION the only thing wrong with this method is the vaproizing mercury fumes are POISIONUS.

No single acid on its own will put the gold into solution, combining two acids will. Nitric and Hydrochloric acids will and then it will take some real chemestry skills to sort out that mess.

i just found another good way to clean gold, a little washing powder had hot water in a jar with a lid and shake it for a little and brings it up well.
cheers
stoppsy

Experimented soaking a little Nugget in some flux used for Silver Soldering, it was only in there for about 12hrs and results looked promising.

I have put a specie in today, i will leave it in for 24hrs and see how it goes.

I will keep yous posted as to how it goes.

Mick,

OK flux sounds interesting.

OH and when you are finished with your nitric acid, adding salt will make the silver that was absorbed into the acid precipitate out as fine white flakes on the bottom of the jar. This allows it to be separated from the acid but after that it can't be removed except by refining. I don't think it would be worth wasting the salt unless you had a big processing plant.

chopppacalamari wrote:OK flux sounds interesting.

OH and when you are finished with your nitric acid, adding salt will make the silver that was absorbed into the acid precipitate out as fine white flakes on the bottom of the jar. This allows it to be separated from the acid but after that it can't be removed except by refining. I don't think it would be worth wasting the salt unless you had a big processing plant.

Hi Choppa,

This flux is used when using Silver Solder to braze Copper to Brass, i have been using it for 30 years in my trade.

Don't think it has Nitric Acid in it as i have been applying it with my finger all them years .

When it is applied to reasonably clean Copper is brightens it up quick.

I will post my results in a few days, got two frail type of Species soaking.

Mick,

It may be ok for getting rid of dirt and general grime of the nuggets but it is hard to se it removing Ironstone or Quartz.

Stainless Steel pickle paste for cleaning stainless steel after welding may work well. It is a gluggy type paste and has Nitric Acid and Hydrofuloric at 5% I can see this stuff working well, maybe even better than Alibrite.

This is the one for cleaning stainless steel after welding
"S-Weld Clean
Specifications
• Contains :
Nitric Acid 30% and Hydrofluoric Acid
5%
• ASTM 380a compliant formulation
• S-Weld Clean is a high adhesion gel, not a
paste
• Pack sizes available 1kg, 2.5kg, 25kg"

Looking forward to see what results you get Mick, I went to have a look on some of my containers of flux to see what is in it, but the labels never stay on them long.

Typically there are two types of flux, RMA flux which is what we would be using to braze brass to copper and it is non corrosive.
Then there is a RA type flux which is highly corrosive and materials should be cleaned after it's use.

Cheers

hey dave...when can you get that from?

From here, they have an outlet in Sydney

http://www.australwright.com.au/

http://www.australwright.com.au/datasheets/alloys/Welding%20%26%20Joining/S-Weld%20Clean.pdf

cheers mate!

Hi Dave,

I wouldn`t expect it to remove Ironstone or Quartz, i have other stuff for that.

Got some Species that have real fine Gold on them and a fair bit, a tooth brush would do damage.

See how things go.

Mick,

Best way to remove Ironstone is not the Alibright method but Spirit of salts instead. Spirit of salts is just pool acid or Hydrochloric (not to be confused with Hydrofluoric) which will easily remove iron (Hematite and manganese oxides) over a period of time (just beware that Hydrochloric acid is VERY active fume wise). Best way is to change the acid out every day after scrubbing the nuggets in clean soapy water with a stiff bristled brush (make sure you check the left overs as iron stone/manganese will almost always carry a lot of fine gold), if you want you can use a glass beaker (pyrex) over a low flame which will speed up the procedure, just make sure it is in a well ventilated area.

The other option for cleaning gold nuggets without quartz inclusions of just enhancing the look of quartz specimens is to use Oxalic acid (comes in a powder form) over a low heat, this method will not harm or remove the silica but will remove the iron staining.

Hope this helps,

JP

I only cleaned 6 grams of fines with the odd coarse bit with the nitric acid. I guess the nitric acid is good for mercury but much better solutions are had for the gold found outside the river system. Great advice for my mate who does detect though. He always raves on about the best way to clean his clermont nuggets. Now i hope he will start talking about the football instead.

[quote="GoldstalkerGPX"]G'day Spinna,
A great cleaner to use rather than electrolysis is a hydrosonic cleaner. Many on the forum will tell you that when Aldi have specials on them get in there fast and get one. I've cleaned nuggets with hot water and a tooth brush and think they are good looking and then wack them in the ultrasonic cleaner for 3 minutes and you can see the dirt lift from the nuggets.

Just a note to let forum members know that Aldi currently have the ultrasonic cleaners on sale for $25
Thanks for the tip GoldstakerGPX, they really do work a treat.
Cheers spinna

G'day all and sundry. I have just joined the forum, and have read a few of the posts, and come across this thread, and thought it needs a bit more explanation for those that are not quite aware of how dangerous this stuff really is, even though there are a few urls leading to websites etc. If explained a bit here, then we wouldn't have to go elsewhere to follow it up.

nero_design wrote: the FBI in America stated that Hydrofluoric Acid was the most dangerous substance available to the public today and vowed to remove it from public access.

The previous quote stands ever so true. For those that use this substance to clean their hard earned with, beware!! Firstly, in order to obtain Hydrofluoric Acid you "Must" be the holder of a "Class 7 Hazardous Chemicals & Materials Licence" and have a genuine commercial reason to use it as outlined under Australian Standards and Workplace Safety rules. Private use for cleaning scrap gold (nuggets) does not even enter the equation as far as these rules are concerned. In order to gain the appropriate licence, you must work for a company that is registered to use it. If found with this solution in your possession, without the appropriate licence, then look forward to a nice hefty fine. For those of you who are unaware of why it is so dangerous, look no further than the rock that it dissolves. Should it come in contact with your skin, it eats its way through to your bone then starts dissolving the bone itself and slowly works its way through your skeletal frame. Enough said, as for Hydrochloric Acid, it cleans gold well, BUT, also dissolves any copper,silver,platinum etc within the gold, thereby reducing the weight of your nugget etc. I apologise for being the bearer of bad tidings, but alas somebody has to do it.

there is a safer product that might do the same job? used to clean ali boats https://www.whitworths.com.au/main_itemdetail.asp?item=15471&search123=cleaner&intAbsolutePage=1

HF seems to be still avaiable here http://www.bobthewelder.com.au/product.php?printable=Y&productid=160


Blitz Aluminium Cleaner 1L Blitz is safe to use, containing no toxic or hazardous fluorides or acids. 1 litre size. $14.95

Just been down to Supa Cheap in Canning Vale here in W.A. and have found both Ali brite and also Chemtech's blitz.
From memory Ali bright was 9% phosphoric acid where as Blitz 38.2%.

Tony

Sulphuric Acid
Hi guys been reading re: different acids to use and has been used cleaning up nuggets.
I have some sulphuric acid left over as a waste pipe cleaner, after retiring in Plumbing.
Going to try that tomorrow and see what happens , I know its better than spirits, in that it eats a hole through your overalls in no time.
So see what happens.
John

I don't have any gold nuggets to clean yet

However we used to use Coca Cola as flux for soldering and it also was great for cleaning coins. Just leave the coin in overnight and it would remove all the tarnish.

Has anyone tried a can of Coke on on their gold nuggets? If it works it would be a cheap and plentiful solution.

gcause wrote:I don't have any gold nuggets to clean yet

However we used to use Coca Cola as flux for soldering and it also was great for cleaning coins. Just leave the coin in overnight and it would remove all the tarnish.

Has anyone tried a can of Coke on on their gold nuggets? If it works it would be a cheap and plentiful solution.

Coca Cola used to contain phosphoric acid. It was the ingredient that made you thirsty and wanting for more. They were forced to remove it and hence, Coke is no longer the cleaning agent it once was.