Options
Good article on dipping.
grip
Posts: 9,962 ✭✭✭✭✭
grip
Posts: 9,962 ✭✭✭✭✭
Comments
<< <i>Interesting. However, I question the 'residue' point. It is more likely the etch itself happens on both the peaks and the valleys. Residue is highly unlikely with most dipping materials. Cheers, RickO >>
Unfortunately not true. Unless the materials are of absolutely pure grade, they will have unwanted materials dissolved in them that deposit onto the coin being dipped. Anything on the first coin in the solution goes into the solution, and redeposits on every subsequent coin dipped. Now, what we're talking about is very minute amounts of material in most cases, perhaps only a few mono-layers, but it is there and affects the reflectivity, color, and reactiveness of the coin for the rest of its days.
http://macrocoins.com
Doggedly collecting coins of the Central American Republic.
Visit the Society of US Pattern Collectors at USPatterns.com.
<< <i>The best way to visualize what happens to the surface of a coin when it is dipped is to think of what happens to a densely-packed sand castle when subjected to its first incoming wave. >>
Yes, I can visualize that! Good analogy. Any acid-based chemical dip will erode the "peaks". Repeated ad infinitum, you get the washed out look of drab silver.
I will say that E-Z-est can be a useful means of removing nasty haze from modern proof coins (no valleys or peaks to wash out here).
---------------------------------------------------------------------------------------------------------------------------------------
BONGO HURTLES ALONG THE RAIN SODDEN HIGHWAY OF LIFE ON UNDERINFLATED BALD RETREAD TIRES
<< <i>The best way to visualize what happens to the surface of a coin when it is dipped is to think of what happens to a densely-packed sand castle when subjected to its first incoming wave. >>
Andy,
That line should be in your signature, bravo indeed.
Well, just Love coins, period.
<< <i>The best way to visualize what happens to the surface of a coin when it is dipped is to think of what happens to a densely-packed sand castle when subjected to its first incoming wave. >>
Can you further explain that analogy? I have trouble seeing the relation to the effect on the surface of a dipped coin.
<< <i>Residue issue is not documented, only speculated. Also, if there is a water rinse, not as likely to leave a lot of residue. I can agree with "peak erosion" though. >>
No documentation required, it's just basic chemistry. Best way to see what will happen is to get a mirror, pour on some of the chemicals you are dipping your coins into, and let them evaporate. Then see how clean the mirror is. Then wash it with a water rinse, and see how clean it comes out. The residue from the water may actually be worse than the original dip. Plus some of the chemicals in the dip are probably not water soluble anyway.
http://macrocoins.com
<< <i>
<< <i>Residue issue is not documented, only speculated. Also, if there is a water rinse, not as likely to leave a lot of residue. I can agree with "peak erosion" though. >>
No documentation required, it's just basic chemistry. Best way to see what will happen is to get a mirror, pour on some of the chemicals you are dipping your coins into, and let them evaporate. Then see how clean the mirror is. Then wash it with a water rinse, and see how clean it comes out. The residue from the water may actually be worse than the original dip. Plus some of the chemicals in the dip are probably not water soluble anyway. >>
Yer reaching now dude since the term "probably" tells me you have no idea...................
The name is LEE!
<< <i> Plus some of the chemicals in the dip are probably not water soluble anyway. >>
If the chemicals weren't soluble in water, they wouldn't be in the dip, now would they?
<< <i>Great article , thanks! >>
It's not a great article, deserves an F. Writer has no fun damental understanding of what's going on. Claims dipping causes loss of luster by filling groves with residue. It's just wrong.
<< <i>
<< <i>
<< <i>Residue issue is not documented, only speculated. Also, if there is a water rinse, not as likely to leave a lot of residue. I can agree with "peak erosion" though. >>
No documentation required, it's just basic chemistry. Best way to see what will happen is to get a mirror, pour on some of the chemicals you are dipping your coins into, and let them evaporate. Then see how clean the mirror is. Then wash it with a water rinse, and see how clean it comes out. The residue from the water may actually be worse than the original dip. Plus some of the chemicals in the dip are probably not water soluble anyway. >>
Yer reaching now dude since the term "probably" tells me you have no idea................... >>
Not reaching at all. I have no idea what's in your dipping solution after a few dips. Neither do you, which is why the experiment is a good way to tell how clean the solution is and if it would leave a residue. I don't "dip" so can't try it myself. I am pretty sure though if you put water on the mirror and let it dry that it will leave a residue.
I do completely agree that the residue is NOT a big reason for killing the luster, of course.
http://macrocoins.com
<< <i>
<< <i>
<< <i>
<< <i>Residue issue is not documented, only speculated. Also, if there is a water rinse, not as likely to leave a lot of residue. I can agree with "peak erosion" though. >>
No documentation required, it's just basic chemistry. Best way to see what will happen is to get a mirror, pour on some of the chemicals you are dipping your coins into, and let them evaporate. Then see how clean the mirror is. Then wash it with a water rinse, and see how clean it comes out. The residue from the water may actually be worse than the original dip. Plus some of the chemicals in the dip are probably not water soluble anyway. >>
Yer reaching now dude since the term "probably" tells me you have no idea................... >>
Not reaching at all. I have no idea what's in your dipping solution after a few dips. Neither do you, which is why the experiment is a good way to tell how clean the solution is and if it would leave a residue. I don't "dip" so can't try it myself. I am pretty sure though if you put water on the mirror and let it dry that it will leave a residue.
I do completely agree that the residue is NOT a big reason for killing the luster, of course. >>
Huh?
When you say "Plus some of the chemicals in the dip are probably not water soluble anyway", you're reaching. The dip I use is water soluble so anything on the coin that isn't water soluble isn't going to come off.
I guess I need to take some time and do my dip test on a Silver BS IKE but then I suppose the right wing extremist coin collectors will find some kind of fault with it.
The name is LEE!
<< <i>
<< <i>Residue issue is not documented, only speculated. Also, if there is a water rinse, not as likely to leave a lot of residue. I can agree with "peak erosion" though. >>
No documentation required, it's just basic chemistry. Best way to see what will happen is to get a mirror, pour on some of the chemicals you are dipping your coins into, and let them evaporate. Then see how clean the mirror is. Then wash it with a water rinse, and see how clean it comes out. The residue from the water may actually be worse than the original dip. Plus some of the chemicals in the dip are probably not water soluble anyway. >>
It's also basic chemistry to consider the pH of a solvent. The solutes that are left after a solution had evaporated may need to be reconstituted with a solvent with a similar pH. Note that I write "may" as not all solutes have the same sensitivity to pH. E-Zest is an acidic solution[/] (e.g. the solutes are dissolved). Once the solvent evaporated and reconstituted in water (i.e. dried on a mirror and then the solutes "washed away") only the solutes that are soluble at the pH of the water (likely close to pH 7) will go into solution and wash away. The residue will need to be reconsituted with an acidic solution. Try rinsing the mirror with vinegar (i.e. acetic acid) and the residue will wash away.
Lane
See http://www.doubledimes.com for a free online reference for US twenty-cent pieces
<< <i>If using a clean solution, (and 'residues' WILL settle out), and rinsing with DI water, there will be no residues...and you can prove MY statement on a mirror. I just did it... three mirrors, three solutions, ALL CLEAN.... That being said, if using a dirty dip solution, no alcohol rinse, no DI water rinse, then yes, residue will be apparent. The article is incorrect regarding the statement on residue. Cheers, RickO >>
It sounds like you dipped and rinsed the mirror. Did you leave the solution on the mirror and let it evaporate? That's what happens on the coin. I'd recommend dipping a coin and then letting the solution drip onto a flat mirror. After it evaporates then you will be able to see what's in the solution. Just think about your bathroom mirror (or maybe don't...) and how hard it is to get it clean enough so you don't see the water spots.
http://macrocoins.com
Also, in my experience although the pH phenomenon described exists, it is not all that important; and by the way, the pH of vinegar is likely not that of EZ but could be measured. Also, the water solubility (vs. oil/hydrocarbon) of EZ can be measured.
I really think that responders ought to give just a bit of thought to the post they are responding to, and that just saying "well, it doesn't have to be measured it exists", or some such is not constructive IMO. If we are trying to figure out just how important or how practical a phenomenon is, then there should be some parameters established. The article itself seems a bit "psuedo-scientific" in explaining what we generally know to exist.
Well, just Love coins, period.
Can you further explain that analogy? I have trouble seeing the relation to the effect on the surface of a dipped coin.
The relation is that they look the same. But you have to look at the coin under extraordinarily high magnification to see the effect. (Scott Travers has published some before and after photos taken under an electron microscope that illustrate this point.)
As for why they look the same, I'll leave it to the chemists to explain.
Doggedly collecting coins of the Central American Republic.
Visit the Society of US Pattern Collectors at USPatterns.com.
<< <i>I don't know why rpms chose the response (s)he did - there is NO documentation regarding residue and his/her answer is more speculation. How much is how much and how quantified?
Also, in my experience although the pH phenomenon described exists, it is not all that important; and by the way, the pH of vinegar is likely not that of EZ but could be measured. Also, the water solubility (vs. oil/hydrocarbon) of EZ can be measured.
I really think that responders ought to give just a bit of thought to the post they are responding to, and that just saying "well, it doesn't have to be measured it exists", or some such is not constructive IMO. If we are trying to figure out just how important or how practical a phenomenon is, then there should be some parameters established. The article itself seems a bit "psuedo-scientific" in explaining what we generally know to exist. >>
Actually, I did give some thought to my response. But it WAS a gedankenexperiment without data. It looks like I need to do the real experiment myself. No problem, I'll go down and buy some EZ today and document the results. Also, I was not the responder who discussed the pH issue, that was "astrorat". And finally, I am male.
http://macrocoins.com
<< <i> <The best way to visualize what happens to the surface of a coin when it is dipped is to think of what happens to a densely-packed sand castle when subjected to its first incoming wave. >
Can you further explain that analogy? I have trouble seeing the relation to the effect on the surface of a dipped coin.
The relation is that they look the same. But you have to look at the coin under extraordinarily high magnification to see the effect. (Scott Travers has published some before and after photos taken under an electron microscope that illustrate this point.)
As for why they look the same, I'll leave it to the chemists to explain. >>
Assuming that the the dip solution uniformly removes a single layer of metal atoms, then the surface configuration of the coin hasn't really changed at all. Imagine a stack of 100 new egg cartons just off of the assembly line. Remove the top one and the stack is now a tad shorter, but it still looks the same on top as it did before you removed one.
<< <i> <The best way to visualize what happens to the surface of a coin when it is dipped is to think of what happens to a densely-packed sand castle when subjected to its first incoming wave. >
Can you further explain that analogy? I have trouble seeing the relation to the effect on the surface of a dipped coin.
The relation is that they look the same. But you have to look at the coin under extraordinarily high magnification to see the effect. (Scott Travers has published some before and after photos taken under an electron microscope that illustrate this point.)
As for why they look the same, I'll leave it to the chemists to explain. >>
So, extraordinarily high magnification is ok to detect this but not for die varieties?
The name is LEE!
<< <i>
<< <i>Interesting. However, I question the 'residue' point. It is more likely the etch itself happens on both the peaks and the valleys. Residue is highly unlikely with most dipping materials. Cheers, RickO >>
Unfortunately not true. Unless the materials are of absolutely pure grade, they will have unwanted materials dissolved in them that deposit onto the coin being dipped. Anything on the first coin in the solution goes into the solution, and redeposits on every subsequent coin dipped. Now, what we're talking about is very minute amounts of material in most cases, perhaps only a few mono-layers, but it is there and affects the reflectivity, color, and reactiveness of the coin for the rest of its days. >>
That is pure hooey unless you are using old battery acid to make your dip from instead of virgin sulfuric acid which is made by the BILLIONS of pounds and is dirt cheap. If there are unwanted materials aka impurities in the components used to make the dip, they are most likely soluble in the dip before and after it is used as well as in any water used to rinse the coin after dipping.
<< <i>
<< <i> <The best way to visualize what happens to the surface of a coin when it is dipped is to think of what happens to a densely-packed sand castle when subjected to its first incoming wave. >
Can you further explain that analogy? I have trouble seeing the relation to the effect on the surface of a dipped coin.
The relation is that they look the same. But you have to look at the coin under extraordinarily high magnification to see the effect. (Scott Travers has published some before and after photos taken under an electron microscope that illustrate this point.)
As for why they look the same, I'll leave it to the chemists to explain. >>
Assuming that the the dip solution uniformly removes a single layer of metal atoms, then the surface configuration of the coin hasn't really changed at all. Imagine a stack of 100 new egg cartons just off of the assembly line. Remove the top one and the stack is now a tad shorter, but it still looks the same on top as it did before you removed one. >>
But thatd be true down to the last layer.
<< <i>
<< <i>
<< <i> <The best way to visualize what happens to the surface of a coin when it is dipped is to think of what happens to a densely-packed sand castle when subjected to its first incoming wave. >
Can you further explain that analogy? I have trouble seeing the relation to the effect on the surface of a dipped coin.
The relation is that they look the same. But you have to look at the coin under extraordinarily high magnification to see the effect. (Scott Travers has published some before and after photos taken under an electron microscope that illustrate this point.)
As for why they look the same, I'll leave it to the chemists to explain. >>
Assuming that the the dip solution uniformly removes a single layer of metal atoms, then the surface configuration of the coin hasn't really changed at all. Imagine a stack of 100 new egg cartons just off of the assembly line. Remove the top one and the stack is now a tad shorter, but it still looks the same on top as it did before you removed one. >>
But thatd be true down to the last layer. >>
One doesn't really need to be a chemist to explain it. If the height difference between the highest and lowest points was 150 atom layers, you would never get down to a last layer. From a practical standpoint, continued/excessive dipping would result in a coin with no numismatic or practical value long before a last layer stage was ever reached.
<< <i>
<< <i>I don't know why rpms chose the response (s)he did - there is NO documentation regarding residue and his/her answer is more speculation. How much is how much and how quantified?
Also, in my experience although the pH phenomenon described exists, it is not all that important; and by the way, the pH of vinegar is likely not that of EZ but could be measured. Also, the water solubility (vs. oil/hydrocarbon) of EZ can be measured.
I really think that responders ought to give just a bit of thought to the post they are responding to, and that just saying "well, it doesn't have to be measured it exists", or some such is not constructive IMO. If we are trying to figure out just how important or how practical a phenomenon is, then there should be some parameters established. The article itself seems a bit "psuedo-scientific" in explaining what we generally know to exist. >>
Actually, I did give some thought to my response. But it WAS a gedankenexperiment without data. It looks like I need to do the real experiment myself. No problem, I'll go down and buy some EZ today and document the results. Also, I was not the responder who discussed the pH issue, that was "astrorat". And finally, I am male. >>
I believe Ezest is sulfuric acid based and since sulfuric acid solution is not volatile under normal conditions, one would not expect a pool of it placed on a mirror to evaporate completely.
<< <i>
I really think that responders ought to give just a bit of thought to the post they are responding to, and that just saying "well, it doesn't have to be measured it exists", or some such is not constructive IMO. If we are trying to figure out just how important or how practical a phenomenon is, then there should be some parameters established. The article itself seems a bit "psuedo-scientific" in explaining what we generally know to exist. >>
The pH of eZest is 1.5. (pH is equal to the negative logarithm of the hydrogen (hydronium) ion concentration)
It's more acid than lemon juice. Less acid than vomit. And infinitely soluble in water. A good rinse under running water effectively removes ALL of the product in a few seconds. What's in your water becomes the only thing that could leave a residue on the coin, not the dip, which is why steam-distilled bottled water is advisible for a final rinse.
http://www.wizardcoinsupply.com/files/images/E-Z-Est-MSDS.pdf
A) Clean mirror
C) New jar of EZest
D) Gallon jug of Steam-Distilled DI water
E) clean glass container holding ~ 1cup of DI water
F) Semicon-grade plastic tweezers
I dropped 1 drop of the following liquids on the mirror in the following order:
1) DI water from the glass cup
2) EZ fresh from the bottle
3) EZ dropped from edge of a Half Dollar #1 after 1 dipping
4) Rinse water dropped from edge of Half #1 after swishing around for ~30 sec
5) EZ dropped from Half #2
6) Rinse water dropped from Half #2
7) EZ from Half #3
8) Rinse water from Half #3
9) Rinse water after Re-dipping Half #3, rinsing, then rinsing heavily with several cups of fresh DI water
Pictures of the evaporated drops are attached below. There is not much residue from the DI water. What's there is probably from dissolved plasticizers, mold release, BPA, etc from the plastic bottle. The EZ drops leave a lot of residue as expected. The interesting thing is how little dissolved EZ it takes to start to see lots of residue. First rinse water, which has only the small amount of EZ from the surface of the Half, is already showing quite a bit of residue. By the 3rd dip, the residue is so heavy it is starting to take on texture. So this shows the rinse water, even if it seems clean, can get contaminated very quickly. However, even after flushing the coin with several cups of DI water, there is still residue in the drop that came off the coin, more than in the original DI drop.
Looks like I can only attach 3 files at a time, so 3 replies, sorry.
http://macrocoins.com
http://macrocoins.com
http://macrocoins.com
<< <i>
<< <i>
<< <i>Interesting. However, I question the 'residue' point. It is more likely the etch itself happens on both the peaks and the valleys. Residue is highly unlikely with most dipping materials. Cheers, RickO >>
Unfortunately not true. Unless the materials are of absolutely pure grade, they will have unwanted materials dissolved in them that deposit onto the coin being dipped. Anything on the first coin in the solution goes into the solution, and redeposits on every subsequent coin dipped. Now, what we're talking about is very minute amounts of material in most cases, perhaps only a few mono-layers, but it is there and affects the reflectivity, color, and reactiveness of the coin for the rest of its days. >>
That is pure hooey unless you are using old battery acid to make your dip from instead of virgin sulfuric acid which is made by the BILLIONS of pounds and is dirt cheap. If there are unwanted materials aka impurities in the components used to make the dip, they are most likely soluble in the dip before and after it is used as well as in any water used to rinse the coin after dipping. >>
Not hooey. I just documented residues left using EZest. It doesn't take much solute to leave a residue.
I just left the mirror to soak in DI water for an hour, then did a liberal fresh DI rinse and blew the mirror dry with canned-air. The attached photo shows that all the drops from each level of experiment, except the original unmolested DI water drop #1, left residues. These are not soluble in DI water. I may try to see if they will come off with Isopropyl.
So now we have DOCUMENTED PROOF that dipping in EZest not only leaves residues, but that they are insoluble in DI water. QED.
http://macrocoins.com
<< <i>
<< <i> Plus some of the chemicals in the dip are probably not water soluble anyway. >>
If the chemicals weren't soluble in water, they wouldn't be in the dip, now would they? >>
Not true. Are you absolutely sure that the dip contains ONLY water soluble components? After my experiment documented above, I am absolutely sure this is not the case.
http://macrocoins.com
Awesome article. Lots of important info. Thanks for sharing.
<< <i>
<< <i>
<< <i>
It's also basic chemistry to consider the pH of a solvent. The solutes that are left after a solution had evaporated may need to be reconstituted with a solvent with a similar pH. Note that I write "may" as not all solutes have the same sensitivity to pH. E-Zest is an acidic solution[/] (e.g. the solutes are dissolved). Once the solvent evaporated and reconstituted in water (i.e. dried on a mirror and then the solutes "washed away") only the solutes that are soluble at the pH of the water (likely close to pH 7) will go into solution and wash away. The residue will need to be reconsituted with an acidic solution. Try rinsing the mirror with vinegar (i.e. acetic acid) and the residue will wash away.
Lane >>
Tried rinsing in pure vinegar (~5%), then gradually diluted it until a final rinse in pure DI again. That should have run the gamut of pH's, assuming EZest is not more acidic than vinegar. No change. Then I tried Isopropyl and it removed my numbering but no change to the residues. Photo after vinegar and isopropyl rinse is attached.
http://macrocoins.com
<< <i>Not hooey. I just documented residues left using EZest. It doesn't take much solute to leave a residue. >>
Sorry but your pictures cannot be found ( https://us.v-cdn.net/6027503/uploads/oldattachments/ACF261E.jpg ). Did you deleted them?
<< <i>So now we have DOCUMENTED PROOF that dipping in EZest not only leaves residues, but that they are insoluble in DI water. QED. >>
Actually, if your pictures would show up, you would have documented proof of what happens when you let E-Z-Est dry on a coin!
Nobody lets E-Z-Est dry or evaporate on a coin as the product is rinsed immediately.
WHEN you get your photo's to show up (read this thread) run your experiment except this time, put the drop of E-Z-Est on the mirror, then rinse it immediately.
The name is LEE!
<< <i>
Sorry but your pictures cannot be found ( https://us.v-cdn.net/6027503/uploads/oldattachments/ACF261E.jpg ). Did you deleted them?
<< <i>So now we have DOCUMENTED PROOF that dipping in EZest not only leaves residues, but that they are insoluble in DI water. QED. >>
Actually, if your pictures would show up, you would have documented proof of what happens when you let E-Z-Est dry on a coin!
Nobody lets E-Z-Est dry or evaporate on a coin as the product is rinsed immediately.
WHEN you get your photo's to show up (read this thread) run your experiment except this time, put the drop of E-Z-Est on the mirror, then rinse it immediately.
>>
It would be nice if you would follow along...
Your suggestion is included in my experiment. I dipped a coin, rinsed it, then let the last drop of liquid drop onto the mirror. I let the drop dry in order to see if there was any residue, and there was. Only AFTER I did this did I run the experiment to see if the residues were soluble in water, and also in low-acid solution and isopropyl, which they were not. The point was not to see what would happen if EZest dries on a coin, of course no one would do that!
I'll follow your link to see how to properly post the photos. But the photos seem to be showing up just fine for me when I click on the links.
http://macrocoins.com
<< <i>Tried rinsing in pure vinegar (~5%), then gradually diluted it until a final rinse in pure DI again. That should have run the gamut of pH's, assuming EZest is not more acidic than vinegar. No change. Then I tried Isopropyl and it removed my numbering but no change to the residues. Photo after vinegar and isopropyl rinse is attached. >>
Interesting.
According to Frank's post, E-Zest has a pH of 1.5 which is much more acidic than acetic acid (pH 2.4). Assuming the pH of the E-Zest is correct, it's not surprising that a weak acid would not solubilize the dried solutes since the solution was created using a strong acid (e.g. sulfuric acid) - at least according to the package label.
In addition, thiourea has limited solubility in water and thus a "non-dissolving" residue seems much more likely than not.
Lane
See http://www.doubledimes.com for a free online reference for US twenty-cent pieces
In my tests relating to dipping brand new bronze spouse medals into Ez-Est to get the spots off...
It is very, very difficult to rinse the coin properly so that it does not react and turn color within the following week.
I would agree that there is something in Ez-Est that water will not dissolve.
Also, the dip does not remove material uniformly. Reactions go the fastest wherever the surface has an acute angle. "Sharp points melt first" in other words. The tips and edges of the metal crystals suffer first and they lose their edge fast.
<< <i>WHEN you get your photo's to show up (read this thread) run your experiment except this time, put the drop of E-Z-Est on the mirror, then rinse it immediately. >>
OK, I gave in and set up a photobucket account. Maybe something good will come of this after all.
I also did what you asked...sort of. I dipped a coin, then let the EZest that was left on the coin drip onto the clean mirror. Left it there for about 5 seconds, then rinsed it liberally with DI water (maybe a pint) directly from the gallon jug. I let all the excess "water" drip off, leaving only a thin film, which I let dry. The image shows that there is a SIGNIFICANT amount of residue left on the mirror.
So, how many more experiments do I need to do to prove that dipping leaves a residue on the coin?
Realize that the amount of material in that residue is very small. If you rinse the mirror (coin) off, and then blow it dry, the residue is nearly imperceptible, maybe just a few atoms thick of whatever it is. Probably just enough to leave a nice reactive surface to create those "beautiful" colors we see on a lot of dipped coins. By leaving a thin film on the mirror, I simulated what it's like to NOT blow-dry the coin. More of this material would build up in the low surfaces of the coin (valleys in the flow lines) and MAY even affect the coin's luster. Which is I seem to remember a conclusion of the OP's linked article...
RayP
http://macrocoins.com
Or would the cotton towl absorb all the residue?
new water. The dip residue on a properly dipped and rinsed coin is so close to zero that what is in the air, minerals and chemicals in your water, the paper towels you use, the bleach or fabric
softener or dust in the towels you use, and just the normal retoning that occurs when any metal is stripped of its oxidation or sulfide coating are the only actions that matter.
<< <i>It would be nice if you would follow along... >>
I am following along but evidently you did not rinse the coin well enough.
The name is LEE!
<< <i>OK, did the experiment. Experimental components were:
A) Clean mirror
C) New jar of EZest
D) Gallon jug of Steam-Distilled DI water
E) clean glass container holding ~ 1cup of DI water
F) Semicon-grade plastic tweezers
I dropped 1 drop of the following liquids on the mirror in the following order:
1) DI water from the glass cup
2) EZ fresh from the bottle
3) EZ dropped from edge of a Half Dollar #1 after 1 dipping
4) Rinse water dropped from edge of Half #1 after swishing around for ~30 sec
5) EZ dropped from Half #2
6) Rinse water dropped from Half #2
7) EZ from Half #3
8) Rinse water from Half #3
9) Rinse water after Re-dipping Half #3, rinsing, then rinsing heavily with several cups of fresh DI water
Pictures of the evaporated drops are attached below. There is not much residue from the DI water. What's there is probably from dissolved plasticizers, mold release, BPA, etc from the plastic bottle. The EZ drops leave a lot of residue as expected. The interesting thing is how little dissolved EZ it takes to start to see lots of residue. First rinse water, which has only the small amount of EZ from the surface of the Half, is already showing quite a bit of residue. By the 3rd dip, the residue is so heavy it is starting to take on texture. So this shows the rinse water, even if it seems clean, can get contaminated very quickly. However, even after flushing the coin with several cups of DI water, there is still residue in the drop that came off the coin, more than in the original DI drop.
Looks like I can only attach 3 files at a time, so 3 replies, sorry. >>
The name is LEE!
<< <i>Sorry, my mistake. Here are the rest of the image files... >>
The name is LEE!
<< <i>This is all such nonsense. Rinsing a coin under RUNNING water is not just diluting the dip, it washes it away faster that the chemicals can migrate into the
new water. The dip residue on a properly dipped and rinsed coin is so close to zero that what is in the air, minerals and chemicals in your water, the paper towels you use, the bleach or fabric
softener or dust in the towels you use, and just the normal retoning that occurs when any metal is stripped of its oxidation or sulfide coating are the only actions that matter. >>
Please propose a reasonable experiment that might prove your point. So far my experiments have shown otherwise. Maybe you could describe for me your method of dipping and I can try following it and see how clean the coin is after. This is my first experience dipping coins, and I went down to the local B&M and bought a container of EZest, and a gallon of DI water, so I'm ready to try anything.
As I said in my first reply, I don't expect much residue, just a small amount. How much residue it actually takes to cause a coin to retone, etc is a subject for another experiment. I've already shown that there is quite a bit of residue using a fixed DI dip volume, or a much larger poured rinse. Are you saying that you rinse the coin in running tap water? Do you wash the coin in the mild soap solution that is recommended?
I find it interesting that people jumped all over me for making statements about expecting residue after dipping, but no one seems to be jumping all over you for making similar statements that there is no residue. I guess people believe what they want to, even in the face of evidence.
RayP
http://macrocoins.com
Question yourself, do you have processed "soft" water or do you have "mineral laden hard" water. It does make a difference.
Second: Now swish the coin in the Distilled Water
Third: Rinse in 91% Isopropyl alcohol
Fourth: Air dry or lightly pat dry without rubbing.
You'll have to adjust the above process to capture your mirror drips.
As for "I guess people believe what they want to, even in the face of evidence."
Your evidence is just a wee bit bogus since folks do not use standing containers of water to rinse dip or soap solution off of coins. They use "running water" and lots of it.
As for retoning, my experience has shown that coins which have been dipped do not retone very quickly because all the "natural contaminents" (i.e. minting oil, minting grease, bag sulphurs, paper sulphurs) get stripped off the coin thereby inhibiting the toning process.
My experience with dipping has also shown that it takes a LOT of dip and/or a long dip time to affect the appearance of a BU coin but......................... only a little dip to affect the appearance of an AU coin. In other words, not every coin is a candidate for dipping and some coins its downright criminal to dip them.
My experience with dipping also shows that a lot of folks really do not have a clue about dipping and choose to instead foster all sorts of horror stories. They like to freely use the term "over dipped" and "dipped to death" for coins which should never have been dipped in the first place. They like to postulate on the process of dipping and how it damages coins without consideration for the fact that dipping coins has been a mainstay for coin dealers and collectors for 50 years or more and millions of high grade, nice looking coins have been dipped.
As for the article in the OP, IMO it was written by someone with just a little bit of knowledge and a lot of negative feelings towards dipping.
The name is LEE!
<< <i>First: Rinse the coin in running water rinsing all sides including the edge.
Second: Now swish the coin in the Distilled Water
Third: Rinse in 91% Isopropyl alcohol
All the above requires plastic coin tongs. >>
OK, will try it tomorrow. I assume you mean 99.9% Isopropyl, correct? That's what I have available, optics grade. But that's not the end of the experiment. I need to get what's left on the coin onto the mirror for inspection. So, what I will do is let the last bit of excess Isopropyl drip onto the clean mirror for evaporation.
RayP
http://macrocoins.com
<< <i>
<< <i>WHEN you get your photo's to show up (read this thread) run your experiment except this time, put the drop of E-Z-Est on the mirror, then rinse it immediately. >>
OK, I gave in and set up a photobucket account. Maybe something good will come of this after all.
I also did what you asked...sort of. I dipped a coin, then let the EZest that was left on the coin drip onto the clean mirror. Left it there for about 5 seconds, then rinsed it liberally with DI water (maybe a pint) directly from the gallon jug. I let all the excess "water" drip off, leaving only a thin film, which I let dry. The image shows that there is a SIGNIFICANT amount of residue left on the mirror.
So, how many more experiments do I need to do to prove that dipping leaves a residue on the coin?
Realize that the amount of material in that residue is very small. If you rinse the mirror (coin) off, and then blow it dry, the residue is nearly imperceptible, maybe just a few atoms thick of whatever it is. Probably just enough to leave a nice reactive surface to create those "beautiful" colors we see on a lot of dipped coins. By leaving a thin film on the mirror, I simulated what it's like to NOT blow-dry the coin. More of this material would build up in the low surfaces of the coin (valleys in the flow lines) and MAY even affect the coin's luster. Which is I seem to remember a conclusion of the OP's linked article...
RayP >>
Not so fast my friend.
What you purport to be residue left on the coin after dipping is most like the silver surface layer that is removed by the acid in the dip. This dissolves in the dip as silver sulfate. Dip a silver coin into some Ezest and let the excess dip drip from the coin into a clean glass like a clear shot glass. Next dilute this with a tad of yer distilled water. Next procure some plain table salt; not the iodized kind. Completely dissolve a smidgen of this plain salt in a small secant of yer distilled water and add it to the dip residue in the shot glass. I'd bet it turns a milky cloudy white indicating the formation of silver chloride and the presence of dissolved silver.