The Great Steel Penney Experiment Allright I just finished my 1943 Steel Penney Experiment. For those who do not know, I was hoping to try to clean up some very corroded penneys that would normally be worthless. I used Vinegar, Gun Solvent, and 30% Hydrochloric Acid in various ammounts. The vinegar was margionally sucessfull after about 20 minutes some of the penneys showed a little better shine and a few bubbles but there was no major change. The solution was: 60ML Distilled Vinegar, 20ML Filtered Water, and a small ammount of salt. The Gun Solvent was slightly less sucessfull showing almost no effects other than a little more shine on allready clean areas. The penneys were soaked for almost 30 minutes with very little sucss. The HCL was much more sucessfull! 30ML of 30% HCL in 120ML of filtered water cleaned a lot of the corrosion off of the penneys, but left some tarnish and some rust still on. The second HCL attempt was much more sucessfull. This was 90ML HCL and 90ML Water. This removed virtually all rust, however I was unsucessfull in keeping them from loosing luster and becomming a dull grey color. My final attempt was to submerge one penny in 30ML of HCL for about a 1 minute 30 seconds. The Penney was then dumped into a solution of Filtered water and Baking soda. This was by far the most effective attempt. Had the penny not been of better grade (technical grade of VG+ I would say) This could almost be passed off as an UNC. Apparently neutralizing the acid before drying the coin is the most effective way of keeping luster because the coin is still very shiney now almost an hour after I have completed the experiment. I will edit this thread with pictures soon. Unfortunatley my web server is down for the night so... be expecting them soon. I plan wide scale tests with larger groups of penneys and possible other types of metals in the near future. If you have any suggestions or comments on this, feel free to send me an email or private message.
30% Muric Acid is available at any local home depot for use in balancing the pH of pools. This seems to work as well as HCL, if you want the real deal, try anywhere you can buy unprinted circuit boards.
You can get it from sigma aldrich and numerous other places. It's also found in driveway cleaner I believe.
Most strong acidic solvents will work, I used what I had around. A Warning: Acids react to metals in different ways, many produce toxic fumes that WILL make you pass out, so remember to keep everything ventellated and such... Also, after you take the coins out of the acid, immedatly put them into a solution of baking soda and water so that you neutralize the acid, otherwise the acid will oxidize the metal again once it comes in contact with air.
hey PenguineMinT, I've used HCL acid on rusted steel pennies also, and got the same result as you did. Works great to take the rust off, but there is one downside: it completely dissolves off all the zinc plating, right down to the bare steel. Since the protective layer of zinc is no longer there, the coin becomes even more succeptible to rust. Save those coins in a "normal" environment for a few weeks, months, or years and you'll see what I mean. Ideally, you would want to protect the coins by re-plating (galvanizing) them with a new coating of zinc. If you can figure out how to do that, then you will have succeeded in making your own reprocessed steel cents.
I wonder if you can clean pennies and actually make them shine, not just become grainy and brighter like I had with penny cleaning experiences.
Well I did a larger batch today and found out that the trick really is to immerse them into a solution of baking soda so that the effects of the acid are neutralized. Im going to work on a way to zinc plate them. So far I have found a way to plate them with gold using nothing but a 9 volt battery and some common household chemicals (along with a small ammount of gold). Im going to try to get a hold of some old V nickles and make some raqueteer nickle reproductions.
I just don't see how it should work. I mean, from the basic chemistry, rust is just FeO or FeOH. Once the rust has "eaten" away parts of the coin, it's going to be quite useless to do anything except to preserve. Acids might help to break up the bonds, but that is if levels of rust is not severe enough. I actually had to deal this with a metal die that I have as the levels of rust is start to acceralate. In the end, I had to use a metal cleaner and use a toothpick and spend hrs to remove the ever annoying rust. This was then dipped into some WD-40 solution and left as ever since.
Just a factoid. Mineral collectors sometimes use oxalic acid to remove rust from quartz crystals. There are no doubt different things going on with the oxidation of a coin and the adherance of rusty compounds on a quartz crystal. I wonder if it would be worth a try?
That's because quartz is madely made out of silicia or silicion dioxide, which is rarely active with other metals. The rust "dust" that covers the quartz rarely interacts with the quartz and hence you can use such powerful acid to "clean" quartz. Iron on the other hand is another thing. Once FeO or FeOH has formed, it will yank out more iron off possible and hence biting away the coin, which means it cannot be restored except to preserve.
Kids don't forget that when hydrochloric acid reacts with zinc hydrogen gas is released. Explosive stuff.
HCL can also cause the chlorine to become free chlorine gas witch is very poisenous. Basicly its some bad stuff.... So dont try it in your kitchen.... hehe
~~~~WARNING : I DO NOT SUGGEST THIS WITHOUT PROPER TRAINING, THIS IS A HIGH LEVEL SOLUTION, WHICH WILL BE DETRIMENTAL TO COINS IF NOT DONE CORRECTLY. TRY WITH A LINCOLN CENT THAT ISNT TOO VALUABLE~~~ well.. seeing as i passed my chemistry class, and got the science scholar award... Acetic acid (vinegar) will remove all surface rust as long as you have chemical proof gloves. To start a "hotsolution" of HCL, put it in a glass / chemical resistant vial, pour in - table salt, distilled water, and iron filings. Then, you put it in a well ventilated room. After this, go back in an hour, and pour it into another vial strained, so there is nothing but pure NaH Cl2 ( wear a mask!!) This is an extremely powerful solution if done correctly. ( or just use 10 mole HCl) Set-up. ----- Get a box (whole box) of baking soda, and a glass of pure, boiled water that started as distilled water. Pour the baking soda in a wide bowl. Then, take a small amount of DILUTED VINEGAR, only around 1% solution, and set it in a shot glass ( works well :thumb Procedure. ----- You put your NaH+Cl2 ( this is for the sitting period, most of the chlorine goes away ) in a pie tin that is tested before hand, and if it won't work, use a pyrex bowl but be careful.you use another instrument, dip the coin in the NaH+Cl2 for a split second, and then you dip it in the 1% vinegar, and quickly into the baking soda. after this, you rinse it with tap water, and then drop it into the distilled water. ---- Aftercare Some coins develop a residue. Acetone will bring this off. NaH - Cl2 will remove heavy PVC and rust. Once again, i must stress my belief that you need to have some prior experience in chemicals.
Am I to assume that a 1943 steel USA penny has a street-value of one cent? I recently received nearly a full roll of them in change at a 7-11 in Stockton. Some kid must have ripped off his father and bought candy with the proceeds.
IN circulation condition, 1-10¢, and slightly higher if there are no signs of rust, as the copper alloy-steel combo tends to rust quickly. --------- YOU GOT A ROLL OF 1943'S AT 7-Eleven?! I gotta visit my Kwik-E-Mart more often (á la Apu from the Simpsons: Thank you, collect again!).
