I placed a 2001-S Silver Proof Kennedy Half Dollar in a coin envelope 5 years ago and tucked it away in my desk just to see what would happen. The results are scary though not surprising. The obverse is blanketed in a specked brown patina that mutes the depth of the mirrors and reduces the impact of the deep cameo contrast. The reverse effect was very different. Rather than a homogenous pattern like the obverse, a deep chestnut patina has formed in small patches of the devices and lettering. I wouldn't go so far as to call it attractive, but it is certainly unique and far better than the obverse. Since the value of this is intrinsic, there really is no financial risk in destroying the appearance of the coin, other than the fact that it will be difficult to sell this as silver bullion to most silver stackers. But the experiment does a good job in showing why proper storage of your coins is important. People love to rave about toning and many want to find a cheap way to create a beautiful rainbow toned coin. Unfortunately, most attempts to do so will yield results similar to my 5 year experiment, a brown POS. Comments welcome!
Heh, that's a very neat experiment! Great way to show newbies that putting money towards correct storing does matter!
Paul, which of the two sides faced up and which faced the desk drawer. I would assume that the drawer contributed to the speckled appearance and the reverse was side up. Am I correct?
This was actually just one in a group of coins that I stored in a stack. Many of the others were clad uncirculated State Quarters which developed very little toning at all. This coin showed the most advanced toning of the group. Strangely, I had every coin from a 1973 Bahamas Proof Set in envelopes as well and they didn't tone either. They are going back in their original packaging very soon. I don't believe that this coin was at the bottom of the stack near the wood.
If you really want to test what happens you need to put each coin in it's own separate coin envelope. Then store them all in the same place. You may, or may not, see some differences. Then, you have a buddy, or 2 or 3, who lives in another town/s do the same thing with the same coins. Then you'll see some differences. edit - and it's a good to mix the coins, some copper, clad, silver, even gold.
depends on where you live. I can get beautiful toning for the most part in less than 6 months. it is altogether a different story that I don't like toning. it also depends on the kind of envelope you use and the place where you keep the envelope just my 2 cents
dear gd gold has the best toning. I know it sounds incredible but when a gold coin tones partially it can look fantastic, brass is very good too, it gives multiple colors in a very short time but it can also catch verdigris very quickly
Doug, Each coin was stored in its own individual envelope and stacked and stored in my desk. Sorry if I didn't make that clear. The only metals that I included were silver, clad, and manganese brass. It really wasn't meant to be a scientific experiment, I was just goofing around. Still an interesting result.
The fact the silver reacted most strongly does not surprise me. If I may, what kind of envelope is a "coin envelope"? Type of paper matters. Is your office always air conditioned? Its not surprising about the clad. I have never seen real "color" on clad coins. If I ever saw one for sale you would have to jump through hoops while singing kumbaya and wearing a lai before I would believe its real.
What kind of envelope is it? On a related note: I was looking at my coins during my yearly inventory over the weekend. I've got some nicely toned coins starting to happen in my Danscos. Will have to snap some pics. But what was interesting to me was that some coins tone very nicely, and others, right next to the coins in question, tone blotchy, and others haven't toned at all. I wonder if some surface contaminant is the reason.
I've stored similar coins (PL 1965 Canada Silver Dollars) in those small manila envelopes and I got similar results like you did after 12 months. The most unattractive aspect was the white haze that developed over time on the fields. Where I live, I'm close to the water where the air has a sweet/salty smell and very maritime-like humidity during the summer, so that had something to do with the progression. And probably less having to do with the envelope.
Mike, It was a standard manilla coin envelope that I used. I will agree that my Danscos tend to produce much more significant toning, but my coins seemed to tone much more evenly. Here are some examples of my Barber Quarters with before and after photos. Before photos: 2008 After photos: 2013 The 1892 & 1897 were kept in my Dansco album whereas the 1916-D was stored in an Intercept Shield 2x2 holder. Both the quarters in the dansco formed a typical splotchy brown peripheral secondary toning that seems quite typical for the series. The 1916-D was completely protected and is still basically untoned. If you recall from my exhibit thread, the first photo of the 1916-D was taken while it was still in a capital plastics holder and the white balance is off in the photo. It never had a green or yellow tint, it was always white like the after photo.
Here is a before and after experiment Coin was harshly cleaned. I placed it in an old yellow coin envelope( probably 30-40 years old) Placed it on a brick in the garden. The area got full sunlight and Texas 100 degree heat. I put it out in June and left it there until near the middle of September. We got very little rain this summer but it did get wet a few times. The reverse was on the bottom. I think the heat from the brick caused the bluish coloring. I only have $10 in the coin and it was pretty ugly to begin with so nothing to lose. Now I got an ugly toned coin instead of an ugly clean coin. Before After
The "after" looks a little better sonlarson. It's interesting how coins change when you do things like this to them. Sometimes better, sometimes worse. Bruce
This is not a tongue-in-cheek question. setting the harsh cleaning aside, would a TPG consider this to be an AT coin?
I doubt this coin would ever be graded. It has residue from some type of varnish or other type of environmental discoloration. I suspect the harsh cleaning was done in attempt to remove whatever is on the surface. I placed in acetone for several days in attempts to reduce or remove it with no results. My local dealer suggested that it might be varnish. I have heard that people used to varnish coins to preserve them. Whatever was used on this coin is permanent. I would never try to pass this off as NT. It doesn't even look natural.
