I collect early commemoratives and at shows, I sometimes encounter coins from the 20's and 30's that have great lustre but are completely 'blast white'. Is it true that almost all such blast white silver coins from this era (and earlier) have been dipped at some time? That is to say, it is virtually impossible for coins of that age (several decades old or older) to not exhibit some toning? But this confuses me, because if a coin was dipped, wouldn't that impair/dull the lustre of these blast white coins? And some of these I've seen still have blazing lustre. Very confusing for me. I have about 30 of the 50 coin early commem short set and a few of my coins are of the blast white variety. I wonder to myself: can this really be what my coins looked like when they were minted in 1936 (for example)? Or must they by definition had to have been dipped to look the way that they do? Thanks in advance for enlightening me
I have an illinois commerative grades ms 64 by ngc that its completly gem white. i have always wondered this myself
Toning of coins depend on many factors, including time. Everything else aside, few coins since from before 1950, will still be blast white if openly stored. If stored in protective environment, this becomes prolonged, if stored in an area of the world where conditions are less likely to cause toning,( or corrosion if one wishes) , such as dry, little sulfur or acid components in the atmosphere, even less light and heat exposure. Remember that metals are more active at higher temperature and light conditions ( but this is a minority issue compare to the previous). A 10 year old silver ASE may show toning if has been allowed to set out in open air. If the coins you refer to , still have luster, protect them with the rest as best as you can, as there is little way to tell if they have been. dipped. Jim
A lot of coins have been dipped , with the naked eye you can't tell unless they were over dipped , or dipped many times . Dipping is cummalitive , each time a part of the surface and some luster are removed . Look at the GSA morgans , they were stored in bags , some in contact with the sulfur in the bag are toned , most in the middle look almost blast white . So a 100+ year old coin can look blast white without having been dipped . But any dipped coin can be seen if you have an electron microscope . Rusty
In order to understand what dipping does to a coin you really need to see it with your own eyes. The same thing goes for understanding what "blast white" looks like. I would venture that probably 90% of the coins that people say are blast white, are not blast white. That of course is with the inderstanding that blast white is what a freshly minted coin looks like. But it's really easy to understand if you just do a few simple experiments. Do them with coins that have no real value though. Take almost any new coin you want, a dime or a quarter say, one that you get in change. Many of these coins are going to be MS - they do not show any wear in other words. Most folks would immediately say that the coin was blast white. Go to the drug store and buy yourself a bottle of TarnX, it's only a couple dollars. Now take that blast white coin and dip just half of into the Tarnx. Then rinse under running water. Now look at the coin. You will immediately see that the half you dipped is a different color than the half you did not dip. The coin may only be a month old, and it's a clad coin at that. But in that month the coin has toned. But to you it didn't look toned at all. You can only see the extent of the toning by doing the experiment I described. That's the problem with blast white, or rather what people call blast white. Yes, the coin looks untoned and thus blast white, but it is toned. It is just so slightly toned that you can't see it. This is even more evident with copper coins. That cent may look completely untoned to you, but dip half of it and you will see just how toned it really is. So even those Morgan dollars from those original mint bags, the ones people think are blast white - are not blast white. Blast white is the name of a color used by almost everyone to describe what a freshly minted coin looks like. The problem is, the color they are describing is anything BUT blast white. It is in reality merely one of many varying shades of grey. It is the color of a toned coin - but most don't realize it is toning. Coins, any coins and all coins, begin to tone the instant after they are struck. It is the nature of metal. edit - Now as to the luster issue. These coins your experiment with, look at the dipped half and the undipped half and compare the luster. If you only dipped the coin for 1 second all toning will be stripped away. But when looking at the coin you will see no difference in the luster. The difference is there, you just can't see it with the naked eye because it is so slight. But hold that coin in the TarnX for 5 seconds and then remove it. Now you will see a difference in luster between the two halves.
Thanks for the explanation/tutorial, Doug. I always learn a lot from reading your posts. I think I understand your point about needing to have a frame of reference or baseline against which to compare and observe the relative amount of color change taking place. I'm going to try out your experiment. Never seen TarnX at the drugstore (I'm sure they carry it, though), but I see Jewelustre(EZest) sold at the local coin shows all the time. I'm guessing they have similar ingredients and I'll see much the same effects as you describe. Richard
Tarnx has a wax solution added to it for polishing silverware, the EZest is straight acid and thiourea. In the old days with black and white film photography, the thiourea was the main component of "Fixer", to remove unexposed silver in the film. The Ezest as it comes from the jar is too active for beginners trying to see effects. Dilute a little with water into a container. The dilution will slow the reaction down, so you have less of a chance of removing any luster. Jim
You can boil water, dissolve baking powder in it, pour the solution into a cup with the insides layered with aluminum foil to make a toning removing solution. Place some silver in the cup (solution has to be still hot) and a chemical redox reaction occurs and only the toning will be removed. None of the silver reacts, so there is no damage done to the coin's surfaces. When the unwanted toning is gone, rinse in distilled water and air dry. This is preferable to dipping since it doesn't strip away any of the silver on the coin, just the toning (silver sulfide, and other oxidation products). The luster is not impaired with this process since once the toning is removed, the solution cannot eat at the silver. The reason is that the aluminum can only react with the toning, and not the silver itself. The baking soda acts as an electrolyte, and the heat increase the rate of toning removal.
Smal problem with your scenario Keeper, silver is removed whenever toning is removed. It can be no other way because toning is not a color that just sits on top of the metal. Toning is the metal itself that has changed color. So to strip away the color, the top layer of the metal itself has to be stripped away.
