Help Needed,

[River21]

Hey all - I have been researching and accumulating for a long time and I have run into my first quandary. This last batch of sterling and scrap (possibly some coin) and two small pieces which ended up being steel I believe.

I do know that this batch swallowed a large amount of nitric - I believe it’s mostly gone as I eventually elected to try to cement after filtering.

Even when I filter the solution is dark black/green suspension and the black seems to follow all dilutions. I tried to test with HCL after cementing and saw very minor cloud, so I was going to call it and figure out what to do... I’m scared to add to my stock pot. But also I’m not sure what even in there, (it’s hard to filter)

It appears to pass through filters but has a cloudy quality.

However it did not pass get well through a 90M silica Buchner - however it left stains (as shown)

1. Does anyone know how to clean these silica plate filters as the yellow/black stains bug me...

2. Does anyone know what I should do with the cement? Is it good for the silver cell?

3. What the yell is going on?

 

[jmdlcar]

If a magnet can pick up a item then don't process it. I have about 400 to 500 grams of Sterling Silver and about 50 grams a magnet can pick them up so set them aside so I won't process them.

 

[nickvc]

To clean up your solution in may need several passes through the same filter paper, as it starts to clog it filters more of the particles out, the cement should be fine for a cell but rinse well and melt, it’s possible looking at your photos that you had rhodium plated silver so it’s likely you have rhodium in mix.

 

[Martijn]

Hey all - I have been researching and accumulating for a long time and I have run into my first quandary. This last batch of sterling and scrap (possibly some coin) and two small pieces which ended up being steel I believe.

I do know that this batch swallowed a large amount of nitric - I believe it’s mostly gone as I eventually elected to try to cement after filtering.

Even when I filter the solution is dark black/green suspension and the black seems to follow all dilutions. I tried to test with HCL after cementing and saw very minor cloud, so I was going to call it and figure out what to do... I’m scared to add to my stock pot. But also I’m not sure what even in there, (it’s hard to filter)

It appears to pass through filters but has a cloudy quality.

However it did not pass get well through a 90M silica Buchner - however it left stains (as shown)

1. Does anyone know how to clean these silica plate filters as the yellow/black stains bug me...

2. Does anyone know what I should do with the cement? Is it good for the silver cell?

3. What the yell is going on?

Hi River 21. Welcome to the forum.
Safety first.. looks like you have chemistry sitting on the tile floor in livingroom or kitchen? Keep all chemicals out of the house for your own sake.

I was thinking the black could be silver oxide formed by light exposure of the AgNO3. Don't know if some will pass through a filter or not.
Dissolve with dilute nitric and test with HCL to make sure.

Cemented silver is fine, just rinse it well and test for copper with ammiona. Test a bit of the rinse water with a drop of ammonia. Blue means copper in solution.

Where did you digest the silver? Outside or in a fumehood?

Forest area or appartment in a flat?

Do you know how to deal with the chemical waste?

Martijn.

 

[Shark]

The center, smaller ear ring, comes in three varieties. I have seen them gold over silver (also known as vermet or vermeil), gold filled, and gold plated on steel. They are usually marked on the flat piece that goes through the ear if gold filled or gold over silver. The plated ones are usually not marked at all.

 

[River21]

Hey all - I have been researching and accumulating for a long time and I have run into my first quandary. This last batch of sterling and scrap (possibly some coin) and two small pieces which ended up being steel I believe.

I do know that this batch swallowed a large amount of nitric - I believe it’s mostly gone as I eventually elected to try to cement after filtering.

Even when I filter the solution is dark black/green suspension and the black seems to follow all dilutions. I tried to test with HCL after cementing and saw very minor cloud, so I was going to call it and figure out what to do... I’m scared to add to my stock pot. But also I’m not sure what even in there, (it’s hard to filter)

It appears to pass through filters but has a cloudy quality.

However it did not pass get well through a 90M silica Buchner - however it left stains (as shown)

1. Does anyone know how to clean these silica plate filters as the yellow/black stains bug me...

2. Does anyone know what I should do with the cement? Is it good for the silver cell?

3. What the yell is going on?

Hi River 21. Welcome to the forum.
Safety first.. looks like you have chemistry sitting on the tile floor in livingroom or kitchen? Keep all chemicals out of the house for your own sake.

I was thinking the black could be silver oxide formed by light exposure of the AgNO3. Don't know if some will pass through a filter or not.
Dissolve with dilute nitric and test with HCL to make sure.

Cemented silver is fine, just rinse it well and test for copper with ammiona. Test a bit of the rinse water with a drop of ammonia. Blue means copper in solution.

Where did you digest the silver? Outside or in a fumehood?

Forest area or appartment in a flat?

Do you know how to deal with the chemical waste?

Martijn.

Hello, Martijn,

Thanks for your concern, no not in a kitchen or living room, just doing some filtering in a ventilated side room. Digestions and primary reactions are performed under a hood that ventilates a large volume of air 1000+/min at over 20 ft in the air out of a room dedicated to this. I generally keep things small (couple ounces) - hobbyist and its very small scale - I honor safety precautions as I still believe myself to need to learn a lot, but overall the biggest points are covered. (storage of chemicals) - PPE - and various hiccup gear (extinguisher) -WASTE: I am using the 3 step treatment, - keeping any waste initially as "stock" and trying to recoup values there... precipitation with copper.... then move any remaining to precipitate metal hydroxides with iron in "waste".... final treatment when 5 gal is filled is base - filter - throw away (at that point safe) then bring remaining solution back down to 7pH and this is safe to discard.

My question is... if I decide to try and precipitate the silver solution with NaCl or HCl... will this void any remaining possible values from adding to my spent nitrate bucket? I know there is silver in the green/blue with blackish stuff... because Hcl pulls a cloud, however the solution stopped cementing out with copper (despite diluting).

My question is why won't copper cement out any more of the silver?
If I use Hcl or Nacl - can I still add the remaining solution (stock) with copper

 

[River21]

Also - where do I get ammonia - or wha is the easiest way to make it. Some of the processes seem way too involved for such a simple chemical, is there a classic store or brand I can get OTC?

 

[jmdlcar]

You can buy ammonia at walmart in the clean area or any food store. I got mind at 2 quart of ammonia at wamart.

 

[Martijn]

Just get household ammonia. It works fine. Used to test for HCL fumes in the air too.
After fitering and making AgCl you have some chlorines in solution, so it may be best to add to the normal stockpot and not the nitrate storage. If you have free HNO3, you are creating weak AR. Not very strong, but still. You could distill the nitrates and get the HNO3 and the metals back out.

Adding HCL should leave other pm traces in solution to transfer to the stockpot for cementing.
With AgCl good rinsing followed by a full conversion to AgO are the most important things to get 3 to 4 nines fine. Lots of small rinses in stead of few large rinses. And test rinse water if its clean.

Did you agitate the liquid to get the last bit of silver out? Like with an air bubbler in AP or in the stockpot.
Why there is still silver left after cementing, not sure, maybe insufficient acidity is a factor here. Saturation levels reached before diluting, and a to high ph after diluting? Again, not sure.
Hope this helps you a bit.
Martijn.

 

[snail]

Check Ace Hardware, used to get 10% ammonia marked Janitorial Ammonia.
No surfactants just ammonia.

 

[Geo]

The black solids could be a less reactive precious metal. Make some aqua regia and warm it. Filter through the fritted funnel and see if it doesn't dissolve the black particles. The solution with the black particles that is suspended and will not settle, add around twenty ml's of sulfuric acid and heat. It cleans the particles and allows them to attach to other particles. Eventually, the particles will get heavy enough to settle and the solution will clear.

 

[Martijn]

The solution with the black particles that is suspended and will not settle, add around twenty ml's of sulfuric acid and heat. It cleans the particles and allows them to attach to other particles. Eventually, the particles will get heavy enough to settle and the solution will clear.

Great tip Geo. :!: Just what i needed. I was struggling with small test solutions from anode slimes. That solved it for me.
They sat for over a week without settling.
Would those small particles clean and attatch the same way in the stockpot? I was considering just adding it to the stockpot, but wasn't sure for that reason.
Martijn.

 

[Geo]

As long as the particles are metallic and not reactive to sulfuric acid. There are other flocculants that will work well in other instances. Magnesium sulfate is also a good flocculant.

 

[Shark]

I have a growing collection of something similar. Mine will dissolve into hot AR and drop back out with a drop using SMB, less so with other precipitants at times. Almost always from gold filled as well. Often I find the same stuff is fluffy and light and will wash out of the gold powders pretty easy. This is where I collect most of mine as I have a container just to collect them in now. I think Geo is on the right track and I need to give it a try as I have around 1/4 inch of such stuff collected and would really like to see just what it consists of.

 

[River21]

Ok most recent update... I was able to pull some silver out by cementing with copper, but cementing stopped and so I tested with 32% HCL and still got cloud... here is what happened when I finally decided to try precipitate with HCL...

Now it has yellow tint (probably from HCL)

I don’t have an exact measurement of my starting silver (I added some and lost track a little) - not by much but a little - another problem is that I may have had a pice of steel in there for awhile and a piece of pre-melted coin silver. Regardless - I am not getting the normal precipitation from HCL addition it’s just a cloudy greenish / yellowish mess

 

[kurtak]

Ok most recent update... I was able to pull some silver out by cementing with copper, but cementing stopped and so I tested with 32% HCL and still got cloud... here is what happened when I finally decided to try precipitate with HCL...

IF (the big IF) "all" the silver has in fact been cemented out with copper - then the cloud you are getting when you add the HCl is more then likely lead which will precipitate as lead chloride when you add HCl or salt

When processing silver (including sterling) lead can end up in your silver nitrate for any number of reasons

Some examples; - solder repair (normally done by a home handyman) where they used a 50/50 or 40/60 lead/tin solder to do a repair

Knife handles are "sometimes" filled with lead or tin or lead/tin alloy (instead of filled with a resin) so even after you remove the sterling shell of the handle there will still be "some lead &/or tin stuck the the inside of the sterling shell

Pendants (like a cross or heart or etc.) "sometime" only have a thin sterling shell with a lead - tin or lead/tin alloy filler

In your first post you said

It appears to pass through filters but has a cloudy quality.

Lead/tin solder may (or not) explain this (& it takes VERY little) IF - there was a "small" solder repair (or other example) the nitric will dissolve the lead (along with the sterling) but the nitric will "not" dissolve the tin & instead turn the tin to "stannic tin" which will cause the "cloudy" that goes through filters

So IF there was a "small" amount of lead/tin in the batch the tin will show up when you first dissolve the batch as the "cloudy" that goes through filter - but the lead will go into solution along with the silver as lead nitrate

The lead will then only show up as lead chloride when you add HCl or salt

Testing for lead chloride - silver chloride will turn a purple/black when exposed to light (UV) whereas lead chloride does not change color (stays white) exposing the precipitate to the sun will tell you very quickly if its silver chloride or lead chloride

Also - lead chloride will dissolve in HOT water (& then precipitate back out when the water cools) where as silver chloride will not dissolve in hot water

So let the chloride you just precipitated settle -poor the acid off - add water to the beaker (may want to do this a couple times) - then put the water & chloride precipitate on the hot plate & see if it dissolve in hot water &/or drops back out when the water cools

Kurt

 

[River21]

Thank you so much - I am still memorizing Hoke - there is a lot to remember about this stuff and I didn't know where to start, thank you

 

[River21]

Looks like it is dissolving in hot water... I though solver chloride had a more chunky appearance

 

[Geo]

Silver chloride will not dissolve in water and will darken in sun light.