Why is it that peace dollars tone so differnt from morgan dollars. The silver/copper content are the same along with the weight.
Supposedly the Peace Dollars had a different solution in the wash than that used for Morgans. Something in that wash retarded toning. Or so the theory goes.
I just did some more searching and found the following. "Morgan Dollars tone more beautifully than Peace Dollars because the planchet of the Peace Dollar was given a more concentrated acid bath at the Mint" Does anyone have any more details or a scientific explanation of how the acid bath effects toning?
Over the years we've discussed this on numerous occasions. Even had one of the members post microscope pics of the surfaces of various coins after one of our discussions because I disagree with the acid bath theory. And if you think about it it makes perfect sense because 98% or more of the surface of a planchet is totally changed and altered the moment it is struck because of the metal flow. And it is the metal flowing across the dies that creates what the final surface of the coin looks like - not how the planchets were prepared. If you look very closely at the surface of a Morgan and compare it to a Peace you'll see very readily that they are quite different. The Morgan has a much more lustrous surface than a Peace. That is because the surface of a Morgan is rougher than the surface of a Peace dollar. This is no mistake or chance happening due to an acid bath. This is because the surfaces of the dies were different. The Peace dollar quite intentionally had a satiny and smoother surface than a Morgan. And the smoother the surface the less readily it tones. And the toning will be quite different. I have tried to illustrate it before, looks like this if the font sizing works - A Morgan looks like this at the microscopic level - /\/\/\/\/\/\ While a Peace looks like this - /\/\/\/\/\/\ well apparently the sizing doesn't work, but imagine the /\ lines being twice as tall for the Morgan. This exposes a lot more surface to the air and light on the Morgan than the Peace. Exposure to the air is what causes the toning, and the larger reflective surface to the light is what refracts it and causes the two types of coins to look differently. The difference in planchet preparation may play a small part, but it was the die preparation that has the lion's share of the reason that Morgans and Peace dollars tone and look so different from one another.
I agree, but if you take into consideration the typical toning on other series with their differences in surface texture, my theory sure makes a lot more sense than the acid bath does.
Honestly, the acid bath theory is a little suspect. It assumes that somehow the acid reacted with surface of the planchet and that compound acts as an inhibitor to the toning process. Your theory is plausible. :thumb:
Especially considering the high profile and higher striking pressure of the 1921 Peace. Any difference on a planchet would be eliminated. I think the die surface difference is a consideration. But it would seem that some researcher would have actually looked at a Morgan vs. Peace die decades ago. Have any coins including modern ones undergone any post strike wash? Doug's little inverted "V" s make sense if they are the height to produce a thin film color reflection like a diffraction grating. Again measuring and calculating this should give a possibility or not. However, if that is the case, even AT peace dollars should not produce any rainbow type of toning. And any toning should be much lesser for AU or dipped Peace $. As the "V" of either type wear down, the toning will become more subdued, even color over surface. Am I off here?:kewl: Jim
As you are probably aware Jim, the answer to a question is often overlooked because it is just too obvious. The answer to this question that one gets most often is that the two coins tone differently because they have different surfaces, which is the same thing I am saying. I have merely explained why they have different surfaces. Not silver coins, the Sackies would be the only ones I can think of. Morgans and Peace dollars didn't either. The wash theory concerns the planchets only - pre-strike. No you are not off. When's the last time you saw a vibrantly toned circ Morgan ? Or just about any circ coin for that matter. Yeah, you can find a circ coin with some colorful toning occasionally, but it will be minimal and they will be few and far between. For a coin to tone colorfully the luster must be there, otherwise it just doesn't happen. Just as the cartwheel effect is created by luster, so is the rainbow effect of toning.