Sciencemadness Discussion Board - How to cut 1oz silver bar into pieces that will fit in a test tube

How to cut 1oz silver bar into pieces that will fit in a test tube

itsallgoodjames - 30-10-2020 at 06:23

So I'm planning to synthesize a handful of silver salts. In anticipation of this, I bought a 1oz bar of silver. If one wanted to cut said bar into approximately 1cm³ pieces, how would one go about that? I've already tried with wire cutters, and while they put a decent dent in the silver, they didn't cut all the way through. I guess the silver is too hard. So how would one cut it? A hacksaw would probably work, but I'd imagine that I'd lose quite a lot of silver doing it they way.

Thanks!

Texium - 30-10-2020 at 07:09

Well any silver salt you make is going to necessarily go through silver nitrate as an intermediate, so you might as well toss the entire bar in a beaker and dissolve the whole thing in nitric acid (outside though, as lots of NO2 will be produced too).

itsallgoodjames - 30-10-2020 at 07:16

That was the plan originally, but the issue is that it'll go through nearly all of my nitric acid to dissolve the whole thing. I guess having to distill some more acid wouldn't be that big of a deal though. I'm already nearly out.

Metallophile - 30-10-2020 at 07:18

Quote: Originally posted by itsallgoodjames

A hacksaw would probably work, but I'd imagine that I'd lose quite a lot of silver doing it they way.

Maybe clamp the corner in a vice, and bend it back and forth until it breaks from fatigue?

itsallgoodjames - 30-10-2020 at 07:21

That's a great idea. I'll definitely try it. Then I can conserve more of my nitric acid

unionised - 30-10-2020 at 07:56

Hammer it into a thinner sheet, and then cut with tin-snips.

Even simpler- put as much of your nitric acid as you wish to use for this project into a beaker, add the silver bar.
leave it to react.
When the initial reaction slows down, warm the solution.

The reaction will stop when you run out of acid.
You can remove the remaining silver- probably by pouring off the solution; you might have to filter it.
That will give you silver nitrate solution.

clearly_not_atara - 30-10-2020 at 08:43

Agree with unionised, or at least try hammering it, it allows you to cut more accurately and it's easier to store and weigh metallic silver than any of its salts.

Quote: Originally posted by Texium (zts16)

Well any silver salt you make is going to necessarily go through silver nitrate as an intermediate, so you might as well toss the entire bar in a beaker and dissolve the whole thing in nitric acid (outside though, as lots of NO2 will be produced too).

If you can obtain methanesulfonic acid, silver methanesulfonate is just as soluble without releasing any toxic gas. Same for trifluoroacetate and probably for ethanesulfonate. In all of these acids you dissolve silver by adding some H2O2.

Silver pyroglutamate is also reported as "soluble in hot water" but no numbers were given in any papers I found. OTC, but speculative. I can find it easily online as a dietary supplement.

[Edited on 30-10-2020 by clearly_not_atara]

Fulmen - 30-10-2020 at 08:43

I would try cutting it with a chisel. For softer metals it can be surprisingly effective.

phlogiston - 30-10-2020 at 08:50

Melt it and pour the molten metal into a large bucket of cold water. It will produce granules of silver, with the size problably depending on a few factors like pouring speed and temperature, but typically they come out about the size of peas.
Its a common method to convert silver into a form thats very convenient for weighing out some amount to use.

[Edited on 30-10-2020 by phlogiston]

itsallgoodjames - 30-10-2020 at 10:13

Quote: Originally posted by Fulmen

I would try cutting it with a chisel. For softer metals it can be surprisingly effective.

That was one of the things I was thinking in the beginning, but I'd have to go buy a new chisel, because I accidentally blunted it trying to do that with copper. From what I've read, silver is only a bit softer than copper, so I have a feeling it wouldn't work all that well

itsallgoodjames - 30-10-2020 at 10:15

Quote: Originally posted by phlogiston

Melt it and pour the molten metal into a large bucket of cold water. It will produce granules of silver, with the size problably depending on a few factors like pouring speed and temperature, but typically they come out about the size of peas.
Its a common method to convert silver into a form thats very convenient for weighing out some amount to use.

[Edited on 30-10-2020 by phlogiston]

I would make it into shot, except for I don't have any way to melt it.

itsallgoodjames - 30-10-2020 at 10:29

Quote: Originally posted by clearly_not_atara

The NO2 isn't really all that much of a concern. I've worked with nitric acid numerous times in the past, so an alternative acid isn't really needed. I checked, and all the other ones you mentioned are more expensive per gram than nitric acid, even if I wanted to buy the nitric rather than make it. Plus, a lot of what I want to do with the silver requires it to be the nitrate salt anyways, so it doesn't really make any sense to go with any of those. I'll probably end up flattening it with a hammer and cut it with tin snips or pliers

Clear_horizons_glass - 30-10-2020 at 12:04

So I cut silver for giving an iridized affect to glass all the time.
an easier solution I would suggest is to just go out and get a silver coin. Grab one end with some pliers, and beat the other end flat with a hammer on something hard like concrete. Then you can just cut the silver with tin snips without to much effort.

[Edited on 30-10-2020 by Clear_horizons_glass]

[Edited on 30-10-2020 by Clear_horizons_glass]

clearly_not_atara - 30-10-2020 at 12:16

Quote: Originally posted by itsallgoodjames

I was unaware of your experience, of course. I mention the alternative acids all the time, because I think a lot of people won't even consider silver chemistry for this reason, which is unfortunate because Ag is an entry point to some of the most interesting chemistry that is accessible with minimal equipment -- obviously photography, but also lots of other stuff.

Pyroglutamic acid is apparently available as a dietary supplement, so maybe I can make my own data about how well it works.

Herr Haber - 30-10-2020 at 12:31

Unless carefull and used to them you are going to have small losses by the chemical processes. Also, it involves waste management.
The hackswaw method isnt that bad and it avoids a lot of efforts. You might also lose some silver here but with a piece of paper under the vice you should get most of it. I use the hacksaw to cut pieces I can put through the neck of my reactor so I'm certain all the nitric acid is used up.

In both cases you'll probably lose a bit but still will have probably more than 30 grams to experiment with including losses.

You seem to have only a little bit of acid left. Cut, bend, tear, flatten if you can and then use your acid. Go for a beaker if your samples are above 1-2 grams

Next time get a one ounce COIN

unionised - 30-10-2020 at 13:24

The trouble with a hacksaw is iron contamination- especially of the "sawdust", if you plan to catch + re-use it.

I guess an HCl wash of the metal would strip Fe but leave Ag behind.

But I still think the easy "solution" is to put the metal in a beaker with however much nitric you want to "spare" for this purpose, and let it react.

Incidentally, does adding H2O2 to HNO3 work?
Does the NOx get oxidised back to HNO3?

B(a)P - 30-10-2020 at 13:32

Quote: Originally posted by unionised

Incidentally, does adding H2O2 to HNO3 work?
Does the NOx get oxidised back to HNO3?

I will give it a try later today and report back.

[Edited on 30-10-2020 by B(a)P]

In a flask1 g of silver was added to 2 mls dH2O and 2 mls HNO3 70%
In a beaker (that is all I had) 1 g of silver was added to 2 mls 35% H2O2 and 2 mls HNO3 70%

Very little happened at room temp, but upon heating both vessels were visibly reacting and no NO2 was visible from the vessel with peroxide.

I will check yields tomorrow and report back.

Next test might be to add more silver than the acid can dissolve and see which mix results in less silver.

[Edited on 31-10-2020 by B(a)P]

Sorry this post got a bit screwed up because of a passing lighting storm. Here is the comparison with a little heat.

[Edited on 31-10-2020 by B(a)P]

[Edited on 31-10-2020 by B(a)P]

Fulmen - 30-10-2020 at 14:14

Quote: Originally posted by itsallgoodjames

silver is only a bit softer than copper

There might be some language issues at play here. I was thinking of a stone chisel, not a wood chisel.

I discovered this while making some metal strips from stainless steel pipe (only suitable stock i had). Hacksaws don't really cut well in soft stainless, so I ended up parting rings of steel tubing and then split them using a stone chisel before hammering them down into flat strips. It's surprisingly effective on softer metals.

itsallgoodjames - 30-10-2020 at 19:08

I think I'm going to hammer it reasonably thin, then cut it with tin snips. Next time I'll buy some silver shot on eBay and save all the effort. No clue why I didn't do that beforehand, given I generally purchase metals in the form of turnings or powder. Not like that'll be any time soon though, as I usually work on very small scales (less than a gram) for most things, due to cost, among other reasons. That's why I was asking about using a test tube, rather than a beaker. Anyways, thanks for the help

TriiodideFrog - 30-10-2020 at 23:21

You could melt the silver and try to pour it into a quartz test tube. If you have to get the silver back out, you can just sacrifice the test tube.

symboom - 30-10-2020 at 23:33

Bolt cutters Will take a chunk out of it.

[Edited on 31-10-2020 by symboom]

j_sum1 - 31-10-2020 at 02:50

Quote: Originally posted by TriiodideFrog

You could melt the silver and try to pour it into a quartz test tube. If you have to get the silver back out, you can just sacrifice the test tube.

This would seem to be the worst of the suggestions so far. The prece difference between silver and quartz glassware would make this prohibitive.

I would think dissolving what you need in HNO3 as you need it would make the most sense.

unionised - 31-10-2020 at 03:07

Quote: Originally posted by TriiodideFrog

You could melt the silver and try to pour it into a quartz test tube. If you have to get the silver back out, you can just sacrifice the test tube.

You could.

You could take your clothes off and run round naked.
It also wouldn't help.

It would have the advantage that you wouldn't need to waste money on a quartz tube and even more so, it wouldn't raise the problem of melting the silver - which the OP said he couldn't do.
"
I would make it into shot, except for I don't have any way to melt it."

Fyndium - 31-10-2020 at 08:11

Never cut any precious metals with sawing or grinding tools. You will lose a huge amount, even if you try to collect the dust.

Get bigger cutters, or borrow bolt cutters.
Try cold chiseling it in a vise.
Put it in a drill press, drill it with clean and sharp bit with low rpm and collect the turnings.
Cast it into round bar and turn it in a lathe for more turnings.

I used to squeeze metal into thinner form with 50 ton hydraulic press. Use smaller mandrels to get more pressure per area, with 10mm square HSS bars I can form pretty much any metal, including non-hardened steel. If you've got even more access, you can turn a drawing mandrel and just press the metal into a wire of desired diameter.

zed - 31-10-2020 at 08:17

Easy. Just make some more Nitric Acid.

Or, employ a jewelers saw, to cut uo your bar. Hold it over a beaker, to catch any filings.

Owning a jewelers saw, is very handy. The hair-like blades are inexpensive, sharp and efficient.

https://www.ebay.com/itm/GERMAN-STYLE-SAW-FRAME-JEWELERS-SAW...

[Edited on 31-10-2020 by zed]

zed - 31-10-2020 at 08:20

Easy. Just make some more Nitric Acid.

Or, employ a jewelers saw, to cut uo your bar. Hold it over a beaker, to catch any filings.

Owning a jewelers saw, is very handy. The hair-like blades are inexpensive, sharp and efficient.

Tsjerk - 31-10-2020 at 09:02

I don't understand anyone wanting to go through the effort of hammering/cutting/sawing/melting if you can just follow unionised's advice and use a limited amount of nitric and filter. You could even just fish out the remaining bar of silver and dissolve any remaining silver powder (if any) with a couple drops additional nitric acid.

Heptylene - 31-10-2020 at 09:20

A chisel will work for a 1oz bar for sure. Be sure to choose the right kind of chisel (for metal). Once you have made a deep cut, you can snap the bar in half by twisting it back and forth several times.

B(a)P - 1-11-2020 at 12:21

Quote: Originally posted by B(a)P

In a flask1 g of silver was added to 2 mls dH2O and 2 mls HNO3 70%
In a beaker (that is all I had) 1 g of silver was added to 2 mls 35% H2O2 and 2 mls HNO3 70%

Very little happened at room temp, but upon heating both vessels were visibly reacting and no NO2 was visible from the vessel with peroxide.

I will check yields tomorrow and report back.

Next test might be to add more silver than the acid can dissolve and see which mix results in less silver.

[Edited on 31-10-2020 by B(a)P]

So I tried this again, this time in the first vessel I added 1 g of silver with 1 g of HNO3 70% and 1 g of DH2O (test 1).
In the second vessel I added 1 g of silver 1 g of HNO3 70% and and 1 g of H2O2 35% (test 2).

After heating test 1 the reaction proceeded as per normal with large amounts of NO2 being released. I kept heating until the reaction was complete. Not all of the silver reacted, I removed the unreacted silver, washed and dried it and 0.15 g of silver remained unreacted.

Test 2 took noticeably more heat for the reaction to proceed and no NO2 was observed. All of the silver was consumed by the reaction.

As long as H2O2 doesn't mess with what ever the intended use is for the AgNO3 it seems adding some H2O2 will save some of your precious HNO3.

BluBoirt - 3-11-2020 at 16:06

Just a side note: if you decide to use H2O2 then you want to avoid alkaline solution because it will reduce Ag+ ions back to elemental silver.

metalresearcher - 3-11-2020 at 23:44

Quote: Originally posted by Heptylene

A chisel will work for a 1oz bar for sure. Be sure to choose the right kind of chisel (for metal). Once you have made a deep cut, you can snap the bar in half by twisting it back and forth several times.

Indeed, 1oz = 31g is about 3cm3.

Or, clamp one third of it in a heavy vise and give it a few hammer blows back and forth and with strong tongs you can break it off, or use a metal cutter after this.

No HNO3 needed, so no noxious NO2.

B(a)P - 4-11-2020 at 00:45

Quote: Originally posted by metalresearcher

No HNO3 needed, so no noxious NO2.

Isn't the ultimate goal to dissolve it in nitric so that the OP can make Ag salts?

Herr Haber - 4-11-2020 at 12:54

Yes but he doesnt have enough to dissolve the whole bar.
(And will most likely need to keep a drop or two if he intends to play with silver salts)

Edit: Just put some silver cement in the oven.

[Edited on 4-11-2020 by Herr Haber]

itsallgoodjames - 4-11-2020 at 15:30

Update for anyone that cares:

I hammered it flat and cut it up. It worked pretty decently, though I wouldn't really reccomend it, given the silver began to work harden and it was a huge pain to get it thinner than a few millimeters. Next time I'm just going to buy silver shot and save the effort. In the picture it looks all dirty and nasty. That's just rust from the hammer used. I've since washed it with some hydrochloric acid, and it's now back to being as shiny as silver normally is.