To lose some gold to teach people some mistakes, this is considered a noble act on your part. That's why I love you, love your work, and enjoy watching your work

Still very nice Chief. To the peeps wondering, etched copper tracks on PCBs will oxidise and disappear quickly if they're not protected and the best way through a process called ENIG. That stands for electroless nickel immersion gold. There's a nickel layer between the gold and copper so the gold doesn't diffuse into the copper track underneath. First the board is immersed in the liquid nickel ion solution, rinsed and followed by the gold layer which makes its stick to the nickel. That's another reason why sreetips first method of removing the copper and nickel first is the best way to go. Too many possible reactions happening with the second method including production of nickel chloride which can be carcinogenic if inhaled.

Conclusive result Sreetips, thanks for putting the work in just to make the point.

I do like that you show the bad ways to do the recovery. It really extends the knowledge base.

Solution held on to almost half the gold. . Just like it held on to the color green. The process worked but isn't efficient. Thank you for the excellent chemistry demonstration Sreetips 🐉🇺🇸🦅 Hope you have a great Fourth of July 🙏 God Bless

You are one hell of an educator, dude. Well put.

Good illustration and good content Chief. Hope you have an enjoyable 4th. Thank you for protecting our Nation.

wow scared me for a second when you were filtering the solution for the first time. when the funnel moved my heart dropped lol

it was good to see the comparison bewteen the 2 videos/methods very interesting , cheers 😊

A very informative video. Not to mention it was interesting too.

I learned a bit from the video and from the communities comments. A good day.

Talk about going around the block to get next door, that definitely qualifies as a horror story. Kudos and thanks for showing it

It was definitely interesting to watch, and see what happens when you skip the step in the refining of gold. Thanks for sharing this with us. Much appreciated Sreetips!

I've watched your videos long enough to know that you always want to get those base metals out first and the way to do that (as you've demonstrated many times) is through nitric boils since gold doesn't easily dissolve in nitric acid alone. This was a really nice demonstration of why you do it that way - it looked really difficult to do and not very rewarding in the end - hats off to you for taking the time and effort to show this!

This is awesome. I appreciate that you do these videos, purposefully making a mess of it. Its a great lesson for those who are getting into the trade

What this video teaches someone inexperienced (like me): the "gotcha" of this method is the idea that "aqua regia dissolves gold" - but without knowing that it really should instead be "aqua regia ALSO dissolves gold." It doesn't JUST dissolve gold. Gold is kind of the LAST thing it dissolves, apparently.

When i watched yesterday, literally this same question went through my mind, and here you are today answering it! Amazing, thank you!

I think rhis experiment just allowed you to see how mycy nitric you need to do the job with a kilo of cards and a liter of hydrochloric.

I'm curious of the costs, equipment and supplies, involved in processing precious metals. Have you done a video addressing costs? An overview of all of the equipment/supplies would be great too.

First off i am man enough to say when i am wrong Professor . As it went along , i was like so what it is dirty. Quicker & less waste & then you got the yield & woops. Ty for taking us along

As long as I’ve been a subscriber, the stannous test sounds like something a doctor would do with a gloved hand. “Okay, cough for me” 😂 I always enjoy your videos. It makes me want to learn how to *safely* refine metals.

I just wanted to say thanx Mr Shreetips. It's always interesting and a pleasure to watch your channel. I feel a bit of a voyeur when i say i have watched your evolution as a channel for years. I have felt privileged also to meet your b er loved family via this channel. I couldn't put into words how greatful I am to be able to emulate and copy your methods. I now need to watch your series on PGM recovery from filters etc. Thanks to you and your hard work, my family benifits from your shared skills. Forever in your debt and entirely greatful, THANKS to you and your family.

I love these experiments. High school science could have been more interesting if you were teaching. Thanks

This video reminds me of something that happened to a friend of mine, an older fellow named Tom I knew about 15 years ago... Back in the 80s he acquired some gold plated circuit boards, and decided to get the gold off of them. Unlike you, he wasn't the type to do small scale tests, though. He did some library research, bought supplies, hired a friend, and they took some barrels of circuit boards out to the desert, BLM land near Ocotillo Wells, and set up in a disused gravel mine. I guess he and his friend just dumped jugs of hydrochloric acid and nitric acid in there... When it fumed up massively, he just said to his friend, "let's go into town and get some coffee." And they took off. Someone saw or smelled the fume cloud, and the police were called. They tried to charge him with an environmental crime but it didn't stick, the text of the crime mentioned specified it applied to "the waters of the state" and there's really no water out in that area. The only charge that stuck was a type of littering. The judge was sympathetic to his "minerals recovery operation gone wrong".

Liking how this is progressing! Excellent comparisons!

Learning is part of the process. Thank you for sharing your experiences, sir.

Thanks for the demonstration Sreetips.

you can try to refine the gold from the solution using electrolysis and 2 graphane rods (from an old battery for instance). it will be more cost-effective and you do not need to reans all that dirty solution. you can refine the deposited metal afterward. the downside is that a lot of nasty gases will be released during the process and you need to do it under the fume hood.

Very cool experiment, that definitely showed why refining needs to be done in the proper steps.

I agree with Andy, you're probably having fun with nickel during the refining process. The good news is that both ENIG (electroless nickel under immersion gold) and ENEPIG (electroless nickel, electroless palladium, immersion gold) are pretty common so you might be getting a little palladium bonus to help offset the nickel frustration.

Its crazy, you'd really think this would work well, but it really doesn't, this was WAYYY less efficient😮, thanks for showing us!

Very nice. As always awesome content. Your channel is a dependable entertaining experience 😊😊😊

I was wondering if this would work. Appreciate you taking the hit for the rest of us.

Отличная работа.

great video , lesson learned . Losing half the yield could really sting when doing this method a number of times .

I'd like to see an xrf of that button. I've done some experiments myself trying to recover the copper after Ag cementation. Adding SMB to barren blue nitrate solution drops copper as a flour like red powder. Ultra fine red powder. So there has to be some copper in that button being it was never removed. This leads me to also believe that not only is there copper in there, but who know what else came out with the Au and Cu. I could see the copper not melting as quickly as the gold and remaining in the melt dish residues as well, also with some Au clinging to it. Very surprised to see Less total metal in the end result than expected. I actually expected More total weight than less because of this. Probably locked up in complexes 'somewhere' with the missing Au as he said.

Very interesting how the 2 methods vary in yield. I can see how the gold can get lost easily. This method is like driving in a blizzard. You can't see where you're headed with all the metals dissolved together in solution. Even losing a couple of grams of gold in the process is costly in the end. Thank you for showing this method. More kilos to go.👍

Hey sreetips would the cheapest way to get rid of the base metals not be peracitic acid by useing vinegar and with an addition funnel full of hydrogen peroxide I tested this mix on a half silver half copper ring and it fully dissolved in less than 24 hrs and those base metals there are super thin shouldn’t take more than a few hrs with a dollar or 2 worth of chemicals would like to see it tried by a professional like yourself

I have a dedicated acid I use just for removing Gold fingers from edge connectors. It's a Mixture of Hydrochloric acid, 3% hydrogen Peroxide and Dissolved copper. Basically it's used AP. After I use the fresh acid and peroxide mixture, I don't throw it out. I re-use it over and over. When the solution gets a little thick (1-2 uses) I just add a little more acid. When this solution is heated, I can strip a batch of fingers of it's gold in less than 12 hours.. It seems the more copper that is dissolved in solution, the stronger it gets. I don't dispose of the mixture until about 10 uses. It just gets too saturated to filter.

Oh nooo! “Big mistake” I’m watching now

where would science be without casserole dishes?

Always fun to watch you do this be safe everyone 👍🇺🇸 and happy 4Th of July 🎆

Thanks for showing us each method you use sreetips 👍

I’ve definitely tried this during my early days of refining and learned the hard way haha. After 13 years of playing with Ewaste, if you insist on acid route instead of cyanide or bacterial leaching, the best way to have done this properly, would have been to use about 65% sulphuric acid mixed into 10% water, and 25% AR. The sulphuric acid causes a passivation layer on the copper/nickel to allow the AR to leach the gold off, and obviously will precipitate lead out once cooled. Carefully Get it hot and keep the materials in the solution until you see the gold is gone. Then decant, rinse very well, and once cooled, filter and drop, refine after the recovery, etc etc. You’ll get some base metals of course into solution, but it’s a small fraction compared to the mess of trying AR like this.

I feel soo bad that I asked this question. Thanks for the info about why we should not use aqua regia in the first step.

Not sure how this would work, but some of the resins used in the underlying circuit board are dissolvable in sodium hydroxide. It might be interesting to see if you can separate the foils first that way.

I love chemistry and this stuff fascinates me, but I'm a bit too clumsy and so I stay well enough away from these things, but I enjoy watching and learning. Thanks as always Sreetips!

Awesome video nice gold button thanks for sharing sreetips

I like seeing experiments once in awhile. Even if they are less efficient.

hi sreetips. thank you for doing that experiment. good to know.

You The Best ❤

Great experiment ✌️

I love the SMB Jar. I think its better then the stump out container.

What do think will happen to the gold when all the surface base metals are dissolved, and there is still sub-surface copper traces present in the circuit boards?. Don't forget that most trimmed fingers come from multilayer circuit boards. you can really see the copper once the outer layer of copper is gone and you can then see wavy lines of copper underneath the fiberglass.

Amazing steps hopfuly we will see more vidoes thanks away

Interesting to see how big difference there were between the two methods. The question is where the gold went. The liquids looked barren so I don't think it went to the stock pot. That leaves the circuit boards. One thing I've seen is that gold could cement out on the inside of multi-layer boards and when it does it's hard to get it again. I would run a sample of these leached fingers in aqua regia and test with stannous to see if there is some gold left in it. There are many videos of people running all different kind of scrap straight into aqua regia and doesn't seem to have any problem. The difference between you and them is that you are careful with your nitric usage while the usual way is to run with a 3:1 or 4:1 mixture from the start. With such a high nitric concentration I think it inhibits any gold cementing. Whenever I run any unknown material I usually do a second digestion if I suspect that I could have missed something.

Another tip: Second option besides the first one I’d mentioned is to put into AR multiple times, rinsing and filtering after each step. Stannous test after each one, but you know due to the reactivity of metals, that the base metals will tend to go in first prior to the gold, so by the 2nd or 3rd AR step, it’s much easier to work with and drop the gold.

So excited for this.good luck.

Thomas Edison might say "I've discovered a new way to not make a light bulb!"

750 👍's up sreetips thank you for sharing 🤗

This is the first time I've noticed orange fumes in the concentrated nitric bottle

I thought about you doing it this was when I watched your last vid on these things. I figured it would just take everything and then you'd have to refine it some more. I didn't think it would be the massive pita as you showed us here.

My first thought when the gold solution turned black it was the coffee filter dissolving.

And now we know 😂

I was a little surprised you didn't use ferrous sulphate for precipitation of such a dirty extraction. Do you think using FeSO4 would be more selective in dropping out just gold and leaving base metals and nickel in solution?

Excellent video thank you 😊 if you know you know about this!!!

Awesome video. Would the iron sulfate be better in this situation than SMB? Thank you for sharing this knowledge with us six stars sir

Hiiii sir iam india.🇮🇳 iam folling u r chennel... .👍👍

Almost twice as much work for half the yield, sounds like my job.

Another great video. I wonder how the sulfuric acid stripping cell would work? It is the same as gold plated jewelry.

Hey ho, fast times in sreetips lab. Still I have to watch this. 😊

Can you do a video of the different colors aqua regia makes with various metals? I thought the yellow it makes with gold was beautiful but that green/emerald color was just as wild! Thanks for the videos!

Your videos are always Great!! Thanks for the info.... can you also use baking soda to neutralize the nitric acid?

Good work team. I watched Philip benders video as per your recommendation and completely forgot I had watched it once before. Unfortunately though, we don't have that same brand of stump out as he recommended, and sulfuric acid isn't free to purchase. You need special permission because people think you would use it as poison. So, basically, shit out of luck. I wanted to use nitric to get gold but ok.

do a video of restoring the lost gold in the solutions please ♥all love

Can you say, what the cost of the fingers, and maybe the cost of materials and times versus the yield when your done! Thansk love the show!

Residual nitric acid can be nuetralized with carbamide - cost effective method.

This is so interesting.

Nice experiment

Hello, in some video you should mention the volumes of acid of each solution. When KZfaq allowed me to upload these videos, it showed with an electronic piecimeter the degree of acidity of each acid. And the mixture at 3X1, since the law of chemistry is more restricted, the developers do not pay us for this content so we do not upload it . 🤙

Great vid as usual Mr. Driver. This what makes me laugh about the “bucket” vids out there. They must lose so much metal because they don’t separate the foils first. Electronics are filthy anyway and this is proven by Streetips’ first filtered solution.

Gold will be bound inside the fibre of the boards only way to get it out is to slow leach them with sodium nitrate and hcl

So sick of people with hair braided ideas you do it wrong on purpose just to show them. Love it.

I wonder if putting the nitric acid into a drip setup would avoid some of the “babysitting” you need to do? It may require a longer evaporation period, but at least you could possibly make better use of time. Just a thought. This was a captivating experiment, for sure 👍🏻

The scientific thing to do now is to figure out where the retained gold actually is, and why. I don't see how gold stannate could be in play here. Possibly absorption into the circuit board materials?

Your Chanel is awesome!!! Big fan! So I was browsing the internet and came across something called purple gold. Apparently it’s a mixture of gold and aluminum, and turns gold purple! Maybe something you want to try and make a video? I think that would be really cool!

Silver chloride is hard 2 deal with... also theres a LOT of tin... makes for hard times when u go out of process...

After that first filtration, I would have put the fingers and the filter residue in boiling AR (on the back burner) to recover any remaining gold while working the filtrate.

If you had produced this mixture in a zero atmosphere environment then leave it for long enough exposed to sunlight, I believe you would create inorganic life!

Thanks 🎉

Looks familiar.. 😃

28:31 it looks like the solution is polluted with pgm or copper chloride (?)

As my chemistry teacher told us in school when we were 15: "Gold is boring. It only reacts to a few things, and even then, it's the most laid back reaction compared to everything else! It's why Gold's so valued as jewellery: it survives almost everything."

Could you have put some sort of metal ( say iron) in the liquid to get the unwanted base metal out, before going to the SMB dosing? Just trying to get a cleaner and quicker result. ??

Would be great if you could do a cost break down at the end.

There is a lot of non-recovery due to the PCB lacquer, you have to try a day first with Caustic Soda that removes all the metal from the PCB, When it has already been released, rinsing with regular water and only processing metal, removing the sterile PCBs is more appropriate. This is because parts of the gold PCB are not connected, they only function as a passive heatsink and have much more thermoplastic varnish lacquers that repel corrosion. It is better to destroy these varnishes first and then only process the metal

Great video! Curious, is it possible to melt the fingers in a crucible with flux and pour into a cone mold for metal separation as a first step?

A great way to show that shortcuts can lose gold. 👍🏻

🤔 Technically wouldn't this method be like you melting the stirling silver and the gold into shot?

I wonder if blending them into a slurry and then gold panning would work?