Can anyone on the site tell me the best way to dissolve the rock around my specimen


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Hey I'm looking for direction on how to dissolve the rock from around my Specimen 

I have had this thing a long time and think I'm ready to change it's appearance. It's Specific Gravity shows 2.36 oz of gold

I have posted the picture before but here it s again. I'm hoping to get enough information to free the specimen I believe it is wire gold.

When and if complete I will share the results with everyone I'm looking to make this a forum project

Thanks in advance 

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The first thing I would do is remove the iron oxide. The safest way to  remove the iron is with Oxalic acid (Wood Bleach). Oxalic acid (Wood Bleach) can be bought at Ace Hardware or on eBay. The other think you will need is a crock pot (Preferably a white one.). I buy crock pots at thrift stores were they cost $5 or less.

Mix 1 cup of Oxalic acid to one gallon of water. place specimen in crock pot and fill with the Oxalic acid-water  solution, turn the crock pot to the highest setting and let boil all night. The solution will turn yellow, dump out the solution when it turns a deep yellow (If the solution is allowed to turn dark yellow it will start to form a crust on the specimen that is hard to remove.) Fill with more Oxalic acid-water  solution. repeat the process until the solution quits turning yellow.  When  the solution quits turning yellow place the specimen in distilled water for 10 min, take out and wrap the specimen in a paper with a rubber band around it and let dry.

If the specimen dries with a yellow stain place it back in a clean oxalic solution in the crock pot for an hour, then soak for 10 min in clean distilled water, take out and wrap the specimen in a paper with a rubber band around it and let dry. Repeat this process until there is no yellow staining on specimen.

Hopefully this will produce a specimen you like.

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Ok I have some information on a way to do this with some simple products.

Thanks Morlock 

"50 % Hydrofluoric acid is very dangerous to use and I wouldn't recommend it unless you have an extensive chemical lab background and the equipment to go along with it.

I suggest you try Armor Etch or Whink rust remover..or a combination of both. Armor Etch is a cream and Whink a liquid and you would get better results with a combination of the two imho.

Both contain very dilute Hydrofluoric acid and it will dissolve quartz but it will take A LONG TIME.... possibly weeks or even months depending on the results you want.

I've used it and it does work very well but you have to be patient with the process. You may even have to buy a couple bottles as it does slow down over time but it's VERY safe compared to the 50% strength.

So I have purchased the materials and I'm ready to go 

 

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A rock crusher works well but maybe that’s not the results you're looking for.

Hydrofluoric acid works well, but it's expensive and very dangerous to breathe the fumes or get it on you. You should also consider the gold you see on the outside of your specimen may not be joined together. So when you melt it down with Hydrofluoric acid. I've burned down a few with it and ended up with a small pile of gold. it burns away the quartz but not the gold. Just put a multi-meter on the gold that is exposed and see if it is conductive/ connected throughout the specimen. You may be better off leaving the specimen  the way it is.

ok Im going to ad more to this. you can also do a specific gravity test on it to try to determine the amount of gold in it. but i am going to tell you this, if you alter the specimen,  with chemicals you may also have a hard time selling it. Its not hard to spot a Hydrofluoriced speci.

AzNuggetBob

Edited by AZNuggetBob
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Thanks Bob

I decided to break away the parts of the specimen that appeared to have very little gold and for the most part I was right.

I mixed the two products and submerged the portion of the specimen with the most gold.

The specific gravity came out to 2.36. I have a few smaller pieces to break down the old fashion way 

 

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Oh BTW the specific gravity test doesn't factor in the iron, or other lessor metals lost in the chemical reduction, only a possible quartz and gold content. that may also help account for the weight loss in the total recovery. 🙂

just thought I'd mention that.

AzNuggetBob

Edited by AZNuggetBob
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On 2/5/2021 at 7:17 PM, fishing8046 said:

Thanks Bob 

Believe me I have no misconceptions on the reality of a specific gravity test and actual gold content. I would be happy with half that. I will snap a picture of the rock that will be crushed to get the smaller deposits 

I have always liked your avatar " I will do Science to it " and we are...

Thanks fishing8046

I have always loved that avatar. Reminds me of when I was young. We are all learning here. Thanks for the thread. 

AzNuggetBob

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  • 2 weeks later...

I think I would leave it the way it is. there is always the option of cutting/ rock saw it/ cab it. but with so much ragged gold exposed that may not be the best option.

I say leave it the way it is.. Very nice speci.

AzNuggetBob

Edited by AZNuggetBob
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  • 2 weeks later...

OK ever body is out of the pool and this is what we are looking like

I have some iron wood I will be using to make a display mount in the coming days. I like that it has exposed the gold in the specimens I don't believe specific gravity is very accurate. Note he gold that was shed from these specimens in the back ground.

Question for all is there a sealer I can now apply to these specimens to prevent any more shedding? 

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fishing8046 you could plasticize it, but the process requires toasting/roasting it in an oven for awhile.  you add a plastic polymer to it, cook it. Its the way they make fake turquoise from copper oxide rock that's not hard enough to be classified as a true turquoise.( has little natural silica replacement). that would help bond it. but I have to say I'm not a big fan of modified rock in general as I call them. It looks fine the way it is. as a matter of fact it looks really nice.
AzNuggetBob

Edited by AZNuggetBob
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