Gold stuck to beaker

I did search but couldn't find anything on this specific issue.

Ok I processed fingers in AR, washed them off and got all the foils. I cleaned these with boiling water and put them in AR. After filtering a nice golden liquid came out and I dropped with SMB. 24 hours later I siphoned off the liquid and allowed the last bit to air dry, woohoo gold! I decided to process this powder again to produce a more pure product and here is where the problem happened. Same process, AR, filter, neutralise, SMB and then I noticed the gold was sticking to the side of the beaker where I imagine there are tiny scratches.

I tried rinsing it off with boiling AR, but it's so pure it doesn't seem to dissolve and I'm stuck as to what I can do here. Any ideas?

you could put strong hcl-cl in your baker, make a ball with filter paper and use that ball with a glassrod to rub the side of your beaker ... be aware that it produce a lot of chlorine so dont do it inside or in a fumehood if you have one.

Ahh thank you I will try that, my fume hood isn't up and running so I'm using an army gas mask and doing it outdoors, safe enough

Hi Sunspot,

1st I think you meant that you processed the fingers in AP.no?
then I would wash or let them sit for some time in hydrochloric acid (HCL)
then I would use hydrochloric acid and sodium hypochlorite (HCL /NaClO ), for fingers, there is no need for AR and you would not have to denox,
but let the NaClO evaporate which is easier.
How many finger did you start with? when all your gold sits in tiny scratches I don't think there was much gold to begin with?
What did you use to denox?
Did you keep your liquids? did you test them?

So, a little more info would be nice and easier to give some help.

Pat

Yes I meant AP not AR sorry about that mistake.

Processing the foils in AR is pretty common from what I have read and it worked well the first time. I started with 600g of fingers, when I say the gold is in scratches what I mean is the scratches seem to have provided a surface for the gold to deposit on and the bands are growing in size, the longest one being about 10cm and 3mm wide. So there is plenty of gold present and some of it deposited onto the bottom of the beaker as well, that I can recover easily enough it's the just stuff stuck to the sides I was unsure how to reclaim.

Yes I kept all liquids and tested them with stannous before putting them into a settlement container. They all tested negative for gold, palladium and platinum, but i'll keep it all and boil it down at a later date to see if anything is left.

Hi Sunspot,

Ok, foils in AR is done, but not really needed, HCL/clorox is perfect for foils or gold powder and like I said much easier to evaporate or just let it sit for 24 hours so the clorox can evaporate . Do a search for HCL/clorox and see what you think about that.

600 g clean cut fingers should be like 2.5 grams gold. If it's stuck on the glass and is thick then just scrape it of with a clean tool? or when powdery,then like ericm said use a filter to wipe it all out and start over again.

good work on the liquids and testing

Hope to have been of any help.

Pat

Sunspot said:

I did search but couldn't find anything on this specific issue.

Ok I processed fingers in AR, washed them off and got all the foils. I cleaned these with boiling water and put them in AR. After filtering a nice golden liquid came out and I dropped with SMB. 24 hours later I siphoned off the liquid and allowed the last bit to air dry, woohoo gold! I decided to process this powder again to produce a more pure product and here is where the problem happened. Same process, AR, filter, neutralise, SMB and then I noticed the gold was sticking to the side of the beaker where I imagine there are tiny scratches.

I tried rinsing it off with boiling AR, but it's so pure it doesn't seem to dissolve and I'm stuck as to what I can do here. Any ideas?

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The 2 main reasons gold will stick to your beaker are dirty glassware and scratches on the glass. Both will cause the problem. You need to keep your glassware scrupulously clean. The slightest bit of oil from fingerprints can cause problems including sticking gold and floating gold. Scratches provide a place for gold to adhere as well. When you find a beaker is scratched, it's time to demote it to purposes other than precipitating. Use a new, clean beaker for precipitation.

Pure gold dissolves as easily as impure gold. Being very pure will not inhibit it's ability to be dissolved.

Dave

Thanks for the information, I guessed the scratch maybe had something to do with it. You can't see it with the naked eye but it's definitely there. I think this time I might get different glass as I got the budget model, might be worth spending that little extra for the better pyrex stuff.

Ms. Hoke, on page 55, states that if you accidentally "bake" metallic gold onto a dish, that it can be removed by covering it with a few drops of HCl, then slowly add a few drop - not more - of a solution of sodium chlorate in warm water. I believe I have read this in several places in her book. Be very careful with any chlorate or perchlorate solution as they can be used for making explosive mixtures. The other options mentioned here are most likely safer, but there's more than one way to skin a snake. (I know, the original saying said cat, but there are probably a lot of cat lovers on the forum and I didn't want to offend them. There are fewer snake lovers.)

I love snake meat.

Sunspot said:

They all tested negative for gold, palladium and platinum, but i'll keep it all

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Don't do that. If you can't process to the point where you KNOW your solutions are barren, go back to the books, or send them to the stock pot, where traces will be recovered. It's a mistake to save useless solutions, as the day will come when you must address them, and it can be overwhelming when you find yourself up to your hips in solutions. Get rid of them (properly) as quickly as you can. If you've done your work properly and they test barren, there's no reason for them to do otherwise at a later date. The only possible concern might be if you have some suspended solids (values) that are slow to settle. If you suspect that's the case, allow your solutions to settle for a day, then discard them, avoiding disturbing what may have settled at the bottom, which you would reclaim.

and boil it down at a later date to see if anything is left.

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I'm going to point something out, and I expect you're going to accept it in the spirit in which it is offered.
When you discuss evaporation, DO NOT SAY BOIL. That gets my ire up in a hurry. as it has the potential to undo the hard work we've accomplished on this board getting readers to understand that boiling is not a good idea. All too many come here and talk about boiling when they mean evaporate. Boiling is the source of lost values, so repeating that word causes those who are still learning to endorse the idea that one boils to evaporate.

Harold

Harold_V said:

Don't do that. If you can't process to the point where you KNOW your solutions are barren, go back to the books, or send them to the stock pot, where traces will be recovered. It's a mistake to save useless solutions, as the day will come when you must address them, and it can be overwhelming when you find yourself up to your hips in solutions. Get rid of them (properly) as quickly as you can. If you've done your work properly and they test barren, there's no reason for them to do otherwise at a later date. The only possible concern might be if you have some suspended solids (values) that are slow to settle. If you suspect that's the case, allow your solutions to settle for a day, then discard them, avoiding disturbing that may have settled at the bottom, which you would reclaim.

I'm going to point something out, and I expect you're going to accept it in the spirit in which it is offered.
When you discuss evaporation, DO NOT SAY BOIL. That gets my ire up in a hurry. as it has the potential to undo the hard work we've accomplished on this board getting readers to understand that boiling is not a good idea. All too many come here and talk about boiling when they mean evaporate. Boiling is the source of lost values, so repeating that word causes those who are still learning to endorse the idea that one boils to evaporate.

Harold

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They tested negative and I'm quite sure they're negative, there may however be such a small trace it's not detectable with sattnous, which is why I would put them in a settlement tank for later processing. I apologise for using the term "boil", you are quite right. What I mean is to put them on a very low heat in order to slowly evaporate the water. I won't have tons of waste solution as I'm not processing enough material, my plan is to use a glass coated nutrient heater (used in hydroponics) to very slowly heat the solution in the tank until there is no water left. In the summer I will not need the heater as I intend to just paint the tank black which will absorb enough energy from the sun to keep it constantly evaporating.

I'm a bit busy atm but I'll be washing the beaker off in the next couple of days.

Thanks for all the information everyone, and no offence taken Harold for pointing out my misuse of the word boil

Sunspot said:

(snip)
I'm a bit busy atm but I'll be washing the beaker off in the next couple of days.

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Not really a good idea a apologize for breaking a forum "speach" rule and then include a "Texting" rule violation

I apologise, I won't use any initialisms again.

Harold_V said:

When you discuss evaporation, DO NOT SAY BOIL. That gets my ire up in a hurry. as it has the potential to undo the hard work we've accomplished on this board getting readers to understand that boiling is not a good idea. All too many come here and talk about boiling when they mean evaporate. Boiling is the source of lost values, so repeating that word causes those who are still learning to endorse the idea that one boils to evaporate.

Harold

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I like the word "simmer"
http://en.wikipedia.org/wiki/Simmering
Simmering is a food preparation technique in which foods are cooked in hot liquids kept at or just below the boiling point of water (which is 100 °C or 212 °F at average sea level air pressure), but higher than poaching temperature.

Sunspot said:

They tested negative and I'm quite sure they're negative, there may however be such a small trace it's not detectable with sattnous, which is why I would put them in a settlement tank for later processing.

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Please pay attention to what I said. Your logic is the very thing that will lead to your waking up one day to an overwhelming amount of solution.

The test with stannous chloride, assuming your solutions have been properly evaporated, and your stannous chloride is not beyond its useful life, is extremely sensitive. It can detect minute traces of values, assuming you know what you're looking for. Why you think that you'll recover values when you combine solutions, diluting even more, the miniscule traces that you assume might remain, is a mystery to me. If a solution tests barren, it's barren. Nothing magical is going to occur to change that. This isn't witchcraft--it's science, and can be tested and repeated reliably.

To help put this in perspective-- a grain of gold (1/480 of an ounce), dissolved in two fluid ounces of solution, will yield a purple/black indication with stannous chloride that is so pronounced it would be much like a diamond in the butt of a black cat. If a solution yields a response that is so faint that it is questionable, it isn't worth pursuing. That's the very solution that should go to the stock pot. Anything else should be (properly) discarded immediately. The sole exception would be solutions in which there may be suspended particles that are slow to settle. In that case, there is no further processing required. You simply allow a day for the particles to settle, then discard the solution in the appropriate manner.

Harold

Sunspot said:

I apologise, I won't use any initialisms again.

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Thank You. 8)

Harold, I wasn't going to dilute things more, I was going to concentrate it by evaporating off excess water, which would mean I don't have much solution at all. However I did not realise the test was as sensitive as that, so I'll just drain off the fluid as most of it's been sitting for days.

Sunspot said:

Harold, I wasn't going to dilute things more, I was going to concentrate it by evaporating off excess water, which would mean I don't have much solution at all. However I did not realise the test was as sensitive as that, so I'll just drain off the fluid as most of it's been sitting for days.

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While evaporating would concentrate the solution, it doesn't address the contents, so you can actually create a monster, or, if carried far enough, even a solution.

If you can concentrate a solution to the point of saturation, it will grow crystals of the heaviest concentrated element. By that means you can actually eliminate some of the contaminants by simply separating the grown crystals from the solution. Given the opportunity, they will reject anything but the compound creating the crystals, so to that end, your plan isn't exactly a bad one. In fact, that's one way to purify silver--growing and re-growing silver nitrate crysals, with each iteration eliminating more of the contaminants that may be present.

As to this process for waste solutions, that's assuming it would be worth the effort in recovering values. As I said, the test is extremely sensitive--so unless the reaction is masked by a very dirty solution, you really are better served by getting rid of them as quickly as you can.

We had a reader on the board (some time ago) who insisted that she did not process blindly, yet she didn't use stannous chloride. Most of us know that a visual inspection of a solution isn't reliable in that you can have traces of platinum or palladium in solution, altering the color, and you have no clue why the solution is colored as it is. Likewise, you can have iron in solution, very closely emulating the appearance of gold in solution, especially if there is some copper of nickel present, where the solution color would lean towards green. Trusting the stannous test is the solution to the problem.

I believe Hoke discusses the concept of testing and eliminating. It's been way too many years for me to recall her posture on that subject, but I know that allowing solutions to accumulate is a huge mistake, especially if you're reasonably active. Soon you have so much you don't know where to start, and you may not have the required vessels to deal with things because they're all tied up in storage.

I think you'll come to understand that your decision to not allow them to accumulate is the proper one.

Harold

:| :roll: *NEED a little free helpful advice*
I should have scrubbed clean these "Yogurt bottles" I used for an "AP processing"...... Lazy Lazy! me foils are sticking hard onto the sides of my Glass. What to do ...what to do?? They've been sittin since February.....