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What Solution for Etching sterling silver?
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I was wondering if anyone knew how to make the solution needed for etching sterling silver. I need the chemical formula.
Thank you,
Kate Hardy- Isle of Wight, U.K.
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4 g potassium iodide
1 g iodine
40 ml deionized water (or more for more dilute etch)
This is not too harmful a solution, but stains skin purple, so wear protective gloves [linked by editor to product info at Amazon].
Also try
10 ml ammonium hydroxide
10 ml hydrogen peroxide
40 ml methanol
I have read about this as a silver etch but not tried it so can't comment on how good it is. I imagine it would be more irritant/corrosive than the iodine based one.
Best wishes,
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Dr. Gary Callon University of Dundee Arbroath, Scotland |
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The following solution etches silver well;
40 ml methanol,
10 ml hydrogen peroxide,
10 ml ammonium hydroxide.
The solution should be made up fresh before etching and will gradually become less and less active over a few days.
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Dr. Gary Callon University of Dundee Arbroath, Scotland |
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Delighted to see the ingredients for silver etching. What are the concentrations? I have a source although no idea what to ask for. Help on this please? Thank you.
Gregory Mooneyfine jewelry designer - Morrow, Ohio
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The concentration of the Hydrogen Peroxide [linked by editor to product info at Amazon] solution is something like 30% in water. The ammonium hydroxide can be a similar concentration. You can also dilute the etch with more water if the etch rate is too fast (e.g. in thin film etching).
Another etching solution for silver is Iron(III)nitrate in water, heated to about 40 degrees centigrade. The initial recipe I read quoted a saturated solution. I tried something like about 20 g in 100 ml, which is fairly dilute compared to this, and it etched the silver well.
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Dr. Gary Callon University of Dundee Arbroath, Scotland |
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Thank you for the information. However, due to our security concerns in the USA, these materials are declared hazardous and will not be sent to my home site shop. Wonderful. Gregory Mooney (returning)fine jewelry designer - Morrow, Ohio +++++ I'm an art student working on a project, and I am looking to etch text into pieces of silverware. Is there a simple way to do this? Is a certain type of flatware (sterling silver, silverplate, stainless steel) any better suited for this goal than the others? I have access to a printmaking studio, which has been my only real experience with etching techniques, but with different materials. student - Boston, Massachusetts |
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You could try a photo lithography technique. You use a light sensitive polymer called photoresist to cover your silverware (I think you can get a sprayable version) - you have to do this in a photographic room with special light. You then need a photomask, which could be either a clear acetate or a sheet of glass with the desired pattern that you require (you have regions where UV light can get through and regions where it can't). Place the photomask over the photoresist and expose to UV light. Develop the photoresist in a similar way to photographic film and you are left with patterned photoresist with exposed metal regions. You can then use the etching solution to etch the exposed metal (the photoresist will act as a barrier where you don't want etching). Rinse with water when done and then remove the photoresist with acetone [linked by editor to product info at Rockler] (nail polish remover).
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Dr. Gary Callon University of Dundee Arbroath, Scotland |
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This seems to be a good site, nice folks helping each other. I am a retired professor (Ph.D. Economics) and want to start etching. I will start with a small photograph, make a stencil, stencil onto a small square silver rectangle (12 square inches), then etch it with a solution. After etching, I will buff it on a grinder for an antique look and then maybe apply a
Liver of Sulphur
[linked by editor to product info at Dick Blick] for a patina.
Simple question, what will be the most difficult step of the process? In advance, thanks for your cooperation.
Douglass G. Norvell, Ph.D.
self employed consultant - Nauvoo, Illinois
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I would suggest that you could scan your photograph digitally and change its colour resolution to straight black and white (2 colours). Then print the image onto a transparency with an inkjet or laser printer. Then cover your rectangle of silver with a photoresist polymer, e.g. Shipley S1813 - this can be done by spin coating it (silver rectangle held on a rotating chuck and prior to spinning, the photoresist is spread on) - or it could be sprayed on with a sprayable version (you have to do this in a dark room, or a room where UV has been filtered out). Still in the darkroom, you then place your printed transparency over the photoresist and expose to UV light (light passes through the clear regions and exposes the photoresist). Develop the photoresist (just like photography) and you then have regions of exposed silver and regions of silver covered with photoresist. Dip the plate in a silver etching solution and leave to etch. After etching remove the photoresist with acetone. This might be easier to do than the technique you mention.
++++++ I have a question about the silver etching solution recommended: 40 ml methanol, 10 ml hydrogen peroxide, 10 ml ammonium hydroxide. I was glad to read the post inquiring about the concentrations of hydrogen peroxide and ammonium hydroxide since I was wondering about those too. I found a few scientific chemical suppliers in the Los Angeles metropolitan area, one of which offers the following: creative graduate student of regenerative ecology - Montebello, California |
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Hi,
A couple of tips concerning etching silver, which I have been struggling with for much of this year.
Electro etching will speed up the etching process, and/or allow more dilute etching solutions. It also tends to reduce undercutting of the etch, and can thus allow deeper etching.
To electro-etch, you attach the piece to be etched to the positive side of a small power supply (anode) and the negative side to a piece of stainless steel. These are then both immersed in your mordant. I use about 1.5 V and a silver ring will typically etch at around
30-100 milliamps.
For photo etching, I've been using Electrolube PRP, which comes in a spray can, and can be ordered in the UK from maplin.co.uk. However, I've just started experimenting with a photoresist film which promises to be much more robust, and last longer in the etching tank. I got this from capefearpress.com (lovely name, huh?) and it is called purtech.
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Mike Karliner - London, UK |
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Nice to hear about the use of the electro technique, which I had read a little about in a good reference book I have seen. I have only ever been concerned with etching very thin films that are typically less than 200 nm. Using an iron (III) nitrate solution gave the best resolution with a photoresist when etching features that consisted of 5 micron wide tracks. This was with Shipley S1813 resist that was spin coated on silicon wafers. The methanol, ammonia, hydrogen peroxide would undercut features of this width but worked well if the features were larger. In response to the question regarding the appropriate methanol solution to use, I think any of the first 4 would be okay. It is just basically methyl alcohol that I used - nothing special about it in terms of purity - anhydrous isn't important either as the ammonia and hydrogen peroxide solutions have water in them anyway. The fifth solution you listed is 50% methanol and 50% water and this may not work as well as it would only contain half the amount of methanol in the recipe - you could maybe add double the amount and then have a solution that is diluted more with water.
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Dr. Gary Callon University of Dundee Arbroath, Scotland |
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Hello
I am trying to etch silver plate.(very fast rate)
I am getting some black remains all over the area .
I am trying to find an etchant which doesn't leave any remains
Do you know ?
Thanks
BGU - Israel
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I've been trying PCB Etchant Solution from Radio Shack. Contents; Ferric Chloride. Intended for copper etching on PC boards. The bottle recommends 20 minutes in the liquid but it seems to take much longer for silver etching. Works beautifully on copper. Keep separate baths for copper and silver as copper may be deposited onto your silver.
Lisa Ciolli- Portland, Oregon
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Lisa, Ferric Chloride [linked by editor to product info at Amazon] is the standard etchant for copper in PCB's and big manufacturers use tanks full of the liquid for the purpose. I'm guessing that in the case of silver, there will be a displacement going on between the iron and the silver such that silver will be dissolving to produce silver chloride with iron falling out of the solution to accommodate it. There is probably a link with their respective positions in the electrochemical series.
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What kind of mask you use when etching..where you don't want silver to by etched. I tried nail polish which worked but not very nice outcome, I tried sharpie too. What is the regular or best thing to use.
Rosy Arrasco- Queretaro, QRO. Mexico
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Mike Karliner: I had never thought of electro stripping instead of acid etching. Could you please advise me on the mordant you use? Also could you share with us the optimum temperature range you have used in the past? I would also like to see one of your pieces where you have used this process. Could you post a pic? Many thanks,
Thomas Hansondesigner craftsman - Salt Lake City, Utah
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Etching on Sterling silver
Hi,
I recently took a metal fabrication class and have heard about etching. I see previous questions regarding etching on metals and would like to know if there is a simpler process rather than mixing several chemicals? I live in an area where there isn't access to chemicals and shipping is rather a concern since a lot of people don't ship certain chemicals.
My only other option would to etch with ferric chloride (from Radio Shack) onto copper then use that piece in the rolling mill to impress the sterling silver?
Thanks so much!
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Thanks to all for the illuminating comments and formulas for etching silver. I've been using the steampunk workshop's techniques for electrochemical etching of brass, and the results using "Press'n'Peel Blue" film have been quite nice. - Norman, Oklahoma |
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I have been etching copper for a while now, (using ferric chloride which is very messy!) usually so that it etches all the way through. I'm now wishing to do the same with silver, is there any way which speeds up the process and how do I dispose of the solution after use? I'm trying to find ways that I can do everything at home rather than using a print studio. I have already had success with press-n-peel transfers.
This site is really useful and informative, thanks!
Jo
Hobbyist - London, England
January 11, 2008
You can etch sterling silver using Ferric Nitrate. Dissolve Ferric Nitrate crystals in distilled water (300 mg of Ferric Nitrate to 400 ml water). Suspend the sterling to be etch upside down in the solution and leave for anywhere from 2 - 5 hours. I tape the metal to a piece of styrofoam and float it upside down in the solution. If you can vibrate the solution, the etching is speeded up (I use a bubbler for a fish aquarium under the plastic container holding the ferric solution
I like this method because it is not as dangerous a chemical to keep in the studio. It will not burn skin, and gives off minimal fumes (I keep it under a fume hood nevertheless).
To see more information you can check teaching notes for Ferric Chloride (for etching copper, brass and bronze) at my website www.makersgallery.com/goss) the technique is the same for either solution - the ferric nitrate just takes longer. I hope that's helpful.
jeweler - Owen Sound, Ontario, Canada
Ed. note: as of the date of posting, the URL for these teaching notes is makersgallery.com/goss/etch.html
February 20, 2008
Hi there,
I am just getting into jewellery making with sterling silver and want to begin making some etched pieces. However, I'm at a loss as to where I would find the relevant materials. What kinds of shops would you suggest I should approach for items such as ferric nitrate for example?
Thanks a lot,
Gemma.
- Melbourne, Vic. Australia
September 25, 2008
I want to know if the formula given to etch silver with potassium iodide, iodine and deionized water is to use as an electrolyte bath with cathode/anode etc.? Or will it work in a glass tray with or without heat or agitation?
Thanks in advance if anyone knows the answer to this.
jeweler - New Jersey
December 17, 2008
Hello,
Could you fill me in a little more on the photo lithography technique, step-by-step, with approximate timings (i.e. how long do I expose the photoresist to UV light?)? What would I need to buy, or is it impossible to do at home? I don't know how to home-develop photos, either - so I need that explaining, too!
- London, U.K.
February 3, 2009
The solution with potassium iodide and iodine will work as it is just by immersing what you want etched into it. I found that it etches silver when I tried it one day - its a common etch for gold and I tried it with some silver I was doing and it worked well though slower than with gold.
For the photo lithography process, you will need some kind of 'dark' photographic room. I imagine that the 'red' light that photographic rooms would be fine to work under. RS Components sell a photoresist aerosol solution that you could spray onto your object in the dark room and then leave to dry. You would then expose through your photomask with a light source, preferably a UV source (though I'm sure it can be done with a white light box) and the time is typically between about 5 seconds and 30 seconds depending on the power of your light. You then develop the photoresist like a photograph in photographic developer (sodium hydroxide), or RS also sell a developer product. The object is then ready to be etched in the silver etch solution. After that has been done and washed, you can strip the unwanted remaining photoresist with acetone (nail polish remover contains acetone). [Some additional notes were sent privately to Elizabeth]
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Dr. Gary Callon University of Dundee Arbroath, Scotland |
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February 16, 2009
Mike Karliner stated his positive results with electro etching but I am curious as to the mordant (Mike called it) used or would another solution help with the etching. Any help would be appreciated since Nitric Acid is not welcome in my studio. Please advise. Tom HansonDesigner/Jeweler - Murray, Utah February 25, 2009 Wow. I accidentally discovered this site trying to find where to buy deionized water in Los Angeles. My partner and I have been trying to find someone who can make silver disks with our logo imprinted on it to add to the jewelry we make. How feasible are these etching processes to do 300 1"x1" flat circles? Or are their companies we can contract with to do this? Deidre Jones- Sylmar, California April 24, 2009 In the days I was making jewelry, I was commissioned to do a pendant in sterling silver with words supplied by the client etched into the surface. I used Riston, a photo polymer used by the electronic industry and ferric chloride. As I remember there was a whitish compound being formed, which would be silver chloride that is an insoluble white material. I was also commissioned to do a large number of small broaches with a design supplied by the client. This I duplicated unto a piece of positive film so they could be cut apart after electro-etching the design and outline of the oval broach, using a sheet of silver. I used common salt as an electrolyte, which formed silver chloride that I was able to melt back into silver using
borax
[linked by editor to product info] and some charcoal mixture in the crucible. - Saskatoon, SK, Canada |
April 28, 2009
Dear Dr Gary Callon
Can you tell me the science behind this etching solution, I mean the possible reaction
40 ml methanol,
10 ml hydrogen peroxide,
10 ml ammonium hydroxide.
I tried myself and it works really good
- Birmingham, UK
May 1, 2009
Deidre, It should be easily possible to do on your discs but it could be time consuming doing them all. As you are in California, there is probably a good chance of there being a microelectronics company that does photo lithography that might be able to do them for you.
Anil, Sorry but I'm not a chemist and don't know what the possible reaction might be. The only guess I could make is silver peroxide or silver hydroxide maybe being formed? I work in microelectronics and came across the recipe in a book that we commonly use here. It has an A to Z of materials and what they can be etched with. The hydrogen peroxide, methanol and ammonia solution worked well but I found it not so good when trying to etch small features. It was also much more active when first mixed together and it gradually became less and less active over a few days. I found the ferric nitrate solution by far the best to work with.
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Dr. Gary Callon University of Dundee Arbroath, Scotland |
May 5, 2009
Dear Dr. Gary Callon
Thanks for your reply. Could you please let me know the book name you are talking about for etching.
- Birmingham, UK
June 24, 2009 "Thin Film Processes" [link is to info about the book at Amazon] by John Vossen and Werner Kern
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Dr. Gary Callon University of Dundee Arbroath, Scotland |
February 13, 2010
Your suggestions for etching silver are interesting and very easy to understand.Please tell me how long the etching solution can be allowed before silverware is washed. How long is the process of etching takes place?
Sri Vishwakar- Coimbatore, India
February 18, 2010
Dear colleagues,
I am trying to selectively etch 30 nm of a silver film in presence of gold pads (also around 30 nm). Do you know any silver etchant that does not affect gold?.
Thank you very much!
researcher - Barcelona
February 19, 2010
Hi, Maria. Gold is very inert. Do you have any reason to suspect that any of the silver etchants described on this page would etch it?
Regards,
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 Ted Mooney, P.E. finishing.com Brick, New Jersey |
April 27, 2010
From recollection, the ferric nitrate solution and the hydrogen peroxide/ammonia/methanol solution do not etch gold so it should be possible to etch silver without attacking any gold that you have there. A potassium iodide and iodine solution is a common preference for etching gold and this will also etch silver. Etching times for up to a few hundred nanometers are fairly quick from a few seconds up to 10s of seconds and the speed is related to how fresh the solution is.
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Dr. Gary Callon University of Dundee Arbroath, Scotland |
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May 4, 2010
Hi Gary - Midlands UK |
June 8, 2010
Hi Maxine,
I have never experienced any problems with the ferric nitrate getting
'old', in fact I am pretty sure that the first time I tried to etch with it, the chemical was donated by a colleague who had it among some others and it had been sitting around for 2 or 3 years. I also regularly made up small amounts of solution such as 100 or 200ml which also kept and were still etching a few weeks later. There is definitely an aging thing with hydrogen peroxide/methanol/ammonia solutions and I found these to be very good when fresh but quite poor after a couple of days. Potassium iodide and iodine solution also does not seem to be affected by ageing and I would imagine would be quite easy to get hold of. I have read that electro etching can be done with a mixture of 3 parts nitric acid to 19 parts deionised water and 2V stainless steel cathode. don't know much about it other than photoresist is generally attacked by nitric acid.
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Dr. Gary Callon University of Dundee Arbroath, Scotland |
June 27, 2010
Dear Gary,
I have purchased Ferric Nitrate in dry form but am unsure at what strength I should use it for etching silver. Could you please advise me?
Thanks,
- Adelaide, South Australia
July 5, 2010
The book that I mentioned above "Thin Film Processes" [link is to info about the book at Amazon] by Vossen and Kern, lists 11 g of ferric nitrate to 9 ml of water which I think is a saturated solution and etch at 44 to 49 centigrade. From my experience, a more dilute solution will take longer to etch and I think the thickness of your silver that you wish to etch has a bearing on the concentration that you should go for. From my experiences, I was etching 200nm thick silver with a solution that was 20g of ferric nitrate in 100ml of water and this etched well in less than a minute. It may be a case of some experimentation on your part. Too concentrated a solution will mean too fast an etch, which could affect the resolution of the lines or shapes. I would suggest maybe starting with the 20 g in 100 ml solution and see how you get on.
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Dr. Gary Callon University of Dundee Arbroath, Scotland |
September 5, 2010
I am attempting acid free etching using a saturated solution of cooking salt with copper electrodes and a 3V power supply. I have got a good etch on the anode after about 90 mins.
When trying this with a sterling silver anode, copper cathode and copper connectors, after 6 hours a black deposit had been made on the silver sheet. Any ideas what this may be and any comments about the possibility of etching silver by this process?
- Derby, England
September 23, 2010
As a guess I would say that you could be creating silver chloride during the reaction, which is depositing. AgCl quickly darkens on exposure to light by disintegrating into elemental chlorine and metallic silver. This reaction is used in photography and film.
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Dr. Gary Callon University of Dundee Arbroath, Scotland |
March 24, 2011 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread
Hi,
I try to etch silver plated copper (etched with cupric chloride and then stripped by sodium hydroxide), but after etching there are black dots and brown stain on the silver.
I would like to ask what is that and what causes it?
etcher - HK
March 25, 2011
Hi, Gary.
We appended your inquiry to a previous thread, and the response from Lisa in Portland Oregon probably answers your question. Good luck with a solution though :-)
Regards,
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Ted Mooney, P.E. finishing.com Brick, New Jersey |
August 31, 2011
I have been etching with water saturated with salt and a battery charger (20 AMP) but it only etches very faintly. So faintly it is easily removed with polishing.
I also tried with some vinegar in water and have varied the etching time from 30 minutes to 1 hour with no change of depth.
Any suggestions to why this would not be working. The battery charger is the same model that I used in college and similarly with he salt water (I even tried distilled water to mix with the salt tonight)
Many thanks
Christina
- renfrewshire, scotland
September 1, 2011
Hi, Christina.
Is the item that you want to etch connected to the red lead? What metal is the jewelry that you are trying to etch? What are you using for the cathode (the metal you are attaching the black lead to)? Can you estimate the amperage that is actually being drawn?
Regards,
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Ted Mooney, P.E. finishing.com Brick, New Jersey |
September 1, 2011
Hi,
The sample being etched isn't attached in this picture but it is silver on both the cathode and anode and I don't have a way of reading the actual AMP while its working.
I was thinking the crocodile clips might not be touching the metal enough (as in surface area) with the teeth.
There are bubbles while it works but he results are so faint.
Thanks
Christina
- Renfrewshire, Scotland
September 6, 2011
Hi, Christina.
I haven't etched silver, so I can't say much except that your recollection of using salt water or vinegar in college may have applied to a different metal than silver. None of the previous contributors to the thread claimed that either of those solutions would work to etch silver. Alligator clips are used on high amperage battery cables for jump starting cars, so I doubt that the limited surface area of the teeth is an issue. The gas bubbles are hydrogen on the cathode, and oxygen on the anode; while they indicate that current is flowing, they also say that at least some of the current is being wasted liberating hydrogen and oxygen instead of dissolving metal.
Regards,
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Ted Mooney, P.E. finishing.com Brick, New Jersey |
October 7, 2011
Christina, the reference source I referred to in this post has 6 solutions listed for etching silver but none of them refer to acetic acid (vinegar). Nitric acid is the only acid listed among the etches. There is one electrochemical etch among them with utilises 3 parts nitric acid to 19 parts water, 2 Volts with a stainless steel cathode. From my experience of etching other metals, I do know that acetic acid is an ingredient in an etch for aluminium, which I have also seen etch nickel if that helps with regards to previous work you mentioned. That etch consists of 80ml of orthophosphoric, 10ml of acetic and 10ml of nitric acids.
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Dr. Gary Callon University of Dundee Arbroath, Scotland |