Can the original strike force applied during coining affect the way a coin tones years later?

Buffalode · November 22, 2009 2:34AM

I am thinking mainly about silver coins but would be interested in any opinions on other metals also. Is it possible that a planchet being struck with more or less force, or the force being applied more gradually, could cause changes in the metal structure that would affect the way the coin tones over time?

adamlaneus · November 22, 2009 2:39AM

There is toning shadow, a phenomenon where some of the surface of the coin becomes less toneable than others. It often happens on Morgan dollars around the rim. The stars on the obverse often have it.

It is probably some sort of passivation of the surface, related to heat or metal movement while striking.

Invisible by itself, it shows up when a coin gets toned.

I suspect Peace dollars tone the way they do, differently than Morgan dollars, because of how the metal flowed during striking.

Buffalode · November 22, 2009 2:49AM

Thanks, this is exactly what got me wondering about this. I bought a 1927 Peace dollar last week that has a light golden tone that just looks different than anything I have seen on any Morgans I own, or any other coin I own for that matter.

Edited to fix a typo

<< 

I suspect Peace dollars tone the way they do, differently than Morgan dollars, because of how the metal flowed during striking. >>

LindeDad · November 22, 2009 3:02AM

May not be the same but I thought I heard some where that many of the Peace dollars were made from reprocessed or melted silver from previous coins so there toning is affected by that also.
And as luster changes and flow lines change with dies wear all can come into play I think.
And as it is always stated probably the biggest factor is where and in what environment the coin is stored in is still probably the biggest factor.

RWB · November 22, 2009 3:24AM

… but I thought I heard some where that many of the Peace dollars were made from reprocessed or melted silver from previous coins so there toning is affected by that also.

All Peace dollars from 1921-1928 were legally required to be struck from silver newly mined in the United States. The mint kept copious records on the source of silver used for dollar coinage.

LindeDad · November 22, 2009 3:39AM

Another of the myths I seem to of heard is killed. Thanks for the info RWB.

Stuart · November 22, 2009 3:57AM

LindeDad: It is my understanding that 1921 Morgan Dollars were minted from reprocessed or melted silver from previous Morgan Dollars. Here are a couple of references that may be helpful for you.

Pittman Act Backgound - Wikipedia

Peace Dollar Backgound - Wikipedia

yellowkid · November 22, 2009 4:02AM

I would think that if parts of the planchet are subject to different forces, than parts of the resultant coin could have different surface porosity(if that is a word), then the piece could tone at different rates. Sure, why not.

LindeDad · November 22, 2009 4:10AM

Thanks now I see how I got that reprocessing in the mix.

CaptHenway · November 22, 2009 4:10AM

<< LindeDad: It is my understanding that 1921 Morgan Dollars were minted from reprocessed or melted silver from previous Morgan Dollars. Here are a couple of references that may be helpful for you.

Pittman Act Backgound - Wikipedia

Peace Dollar Backgound - Wikipedia >>

I would certainly trust RWB's information over Wikipedia, which is a lot of fun but sometimes inadequately fact checked.

Question for RWB: The making of blanks necessarily leaves some leftover silver from the webbing. Was this webbing kept segragated from webbing left over from other denominations and melted down into bars used only for dollars, or was it comingled?

TD

Stuart · November 22, 2009 4:19AM

<< I would think that if parts of the planchet are subject to different forces, than parts of the resultant coin could have different surface porosity(if that is a word), then the piece could tone at different rates. Sure, why not. >>

YellowKid: In reply to your above quoted post, when a coin planchet is struck by the dies the pressure induces metal flow into the design elements of the dies. It is true that as a result of this metal flow, you can sometimes detect varying textures in different parts of the coin. Adam is correct that we oberve this effect frequently with Morgan Dollars, and that sometimes this will have an impact on resulting toning.

It's my observation that in the areas near the rim of Morgan Dollars one may observe a 1mm wide area that has a "smeared" looking slicker texture (for non-PL/DMPL Coins) that typically seems more resistant to toning than the surrounding areas of the coin. This occurs between the outermost design elements and the beaded design rim of both the obverse and reverse.

I would be interested in learning about other Forum members' observations on this topic.

Stuart · November 22, 2009 4:24AM

<>

Tom (Capt Henway): I agree with your above comment, that I have total confidence in RWB's research on Peace Dollars. However IMO the Wiki reference does not conflict with RWB's post.

RWB specified that Peace Dollars were struck from silver newly mined in the U.S. The Wiki reference that I posted specifies that 1921 Morgan Dollars were minted from reprocessed or melted silver from previous Morgan Dollars.

By the way, I've always wanted to ask you How Much Does a Henway ?

Buffalode · November 22, 2009 4:30AM

<< <<

By the way, I've always wanted to ask you How Much Does a Henway ? >>

I assume we are talking Troy ounces?

COALPORTER · November 22, 2009 4:36AM

I would say yes/ maybe.
Atoms on different parts of the coin have different energy states depending on how far they more when the plancet metal is deformed.

That is what allow products like Nick-a-date to work, because it attacks the metal in relation to the stored energy- thus rexposing the date and other high point details like the horns. If Nickadate ate the coin at an even rate, then the date would not be restored. This is also how police can recover the serial number that has be ground off of a gun.

I would imagine that metals with different enery states would react to chemical treatment different and therefore the colors may vary. I dont know if the mint machines vary enough to make any difference thought - maybe they do?

SkyMan · November 22, 2009 4:42AM

Part of the reason Peace dollars tone differently from Morgans is that their planchets were subject to a different wash than Morgans were. Also, the bags that Peace dollars were in were different than the ones that Morgans were in. I don't know about the chemical composition of the fabrics that the bags were made out of, but the Peace dollar bags were of a finer mesh than the Morgan dollars. If you've seen fabric toning on the coins you can immediately tell that the Peace dollars sat in bags that had a significantly finer mesh than the Morgan's bag.

One coin that some people hypothesize about the rolling of the metal sheets affecting the planchets, that eventually became noticeable when the planchets toned up, was the 1960 Franklin. It has a very noticeable look when you see it. It predominantly occurs with the 1960 mint Franklins (only a fraction of them), although I have seen some 1960 P mint Roosies with the same look, and some, but not nearly as many, 1959 Franklins. The look is one of linear striations that occur once the coin starts to tone up. Here is an example, where you can see the linear striations that almost give a "texture" to the coin...

RWB · November 22, 2009 4:45AM

re: Question for RWB: The making of blanks necessarily leaves some leftover silver from the webbing. Was this webbing kept segregated from webbing left over from other denominations and melted down into bars used only for dollars, or was it comingled?

My original comment was not specific enough. All silver dollars struck from 1921-1928 had to comply with the Pittman Act, and the silver had to come from newly mined domestic production. Scrap, webbing, melted rejects, etc. were all included in the same requirements. No other silver was permitted to be used for dollar coins during that period. No exceptions.

(There are multiple bullion and coinage journals devoted to this in the Mint and Treasury archives. I have a complete page-by-page set of the production journal, and I can assure you, the Treasury folks were counting down the coins and Pittman bullion.)

RWB · November 22, 2009 4:50AM

Part of the reason Peace dollars tone differently from Morgans is that their planchets were subject to a different wash than Morgans were. Also, the bags that Peace dollars were in were different than the ones that Morgans were in.

Planchets were prepared in exactly the same way for Morgan and Peace dollars in 1921, except for the diameter and upset angle. Washing, whitening, etc. was the same. It is possible some changes were made in 1922 at one or more of the mints, which connects with speculation about 1922-P dollars and white spots.

Bags were different for most Peace dollars, but no one is sure about the changeover date or exact differences in cloth composition and weave. The Mints were under orders to cut expenses and made many undocumented changes during the 1920s.

LindeDad · November 22, 2009 5:02AM

So am I to understand that Dollars got new silver. Scrapes and reclaimed went to the mintage of other silver coins at that time.

Stuart · November 22, 2009 5:20AM

RWB: Thanks very much for clarifying.

EagleEye · November 22, 2009 5:20AM

Striking force might not influence on the toning patterns. It just doesn't seem like it would have an influence. I think planchet preparation and washing may have something to do with subsequent toning. It seems original coins from the 1870-1915 period tone differently than the coins in the 1920-1930 period, and the ones after 1933 tone differently from the ones from the 1920's. Just compare the toning on a Oregon commem to a typical Alabama or Missouri. Also compare Peace dollars to Morgans. Standing Liberty Quarters and 1932 Washington quarters to Barbers or later Washington quarters.

The ones in the 1920's get dull grey toning, while later and earlier coins tone with more colors.

Any research done on planchet washing?

RWB · November 22, 2009 5:37AM

Lindedad - No. Scrap from the production of Pittman dollars was reused for Pittman dollars only. Purchases under the Pittman act stopped in 1923 when Treasury had bought enough to conform to law; most Pittman silver was bought in 1920-early 1921.

RWB · November 22, 2009 5:48AM

A possible source of toning differences were the designs and how dies were maintained. Morgan dollars of 1921 were from symmetrically basined designs just as in the 1878-1904 period. They were lapped, or rebaisened as part of normal maintenance, thus the large number of proof-like pieces. Dies were also manually retouched.

The dies for Peace dollars (and the subsidiary silver and minor coins introduced during the “Renaissance of American Coinage” period) did not originate with symmetrically basined master dies and master hubs. Dies came from mechanical reductions which had a different character for the surface than did lapped dies. Manual retouching was also minimized.

If you compare a new 1921 Morgan with a new 1921 or 1922 Peace, you will see that the fields are completely different in character – even for specimens showing considerable cartwheel luster. New 1921 dollars from fresh dies have a satin-like surface.

The microscopic differences in exposed metal might contribute to toning differences. (As might being moved to dry storage from the swamps of New Orleans.)

Just some thoughts….

LindeDad · November 22, 2009 6:31AM

Interesting Sunday coin discussion Thanks to all I am out of here to the tread mill.

Bear · November 22, 2009 6:34AM

What would be the effect on coins toning with higher

stamping pressure, using worn dies. Would the stress

on the metal make a difference such as less toning?

RWB · November 22, 2009 8:05AM

Total surface area to react with sulfur, chlorine, bean farts, etc.???

Buffalode · November 22, 2009 10:06AM

A lot of good points and information. One more question though, did the Mint keep records on how much strike force was used when minting the Peace and Morgan dollars? Actually two questions, did the strike force used vary much from year to year, or by Mint, within the series?

Stuart · November 22, 2009 10:25AM

With due credit to RWB, who provided me with this information, 1921 (First Year) High Relief Peace Dollars wre initially struck using 150 tons of pressure in an attempt to obtain fully struck desgn details, which had an adverse affect on wearing and breaking the dies.

They then backed off to 120 Tons of pressure for the remaining 1921 Peace Dollars. Total 1921 Peace Dollar mintage was 1 million coins. Mintage details are provided in RWB's (Roger Burdette's) "A Guide Book of Peace Dollars" Red Book published by Whitman.

RWB · November 22, 2009 10:26AM

Records were probably kept by the Coining Dept, but nearly everything has been lost or intentionally destroyed. We now have only generalities: approx 120 tons for most 1921 Peace, 100 tons for Morgans and 80-100 tons for 1022 & later Peace. But these could easily have differed from press to press and between the mints.

Buffalode · November 22, 2009 11:13AM

Thanks fellas, it is great to be able to gain so much knowledge from this forum. Thanks for being so willing to share what you have learned.

CaptHenway · November 22, 2009 3:27PM

<< <>

Tom (Capt Henway): I agree with your above comment, that I have total confidence in RWB's research on Peace Dollars. However IMO the Wiki reference does not conflict with RWB's post.

RWB specified that Peace Dollars were struck from silver newly mined in the U.S. The Wiki reference that I posted specifies that 1921 Morgan Dollars were minted from reprocessed or melted silver from previous Morgan Dollars.

By the way, I've always wanted to ask you How Much Does a Henway ?

>>

About three pounds......

MrEureka · November 22, 2009 7:39PM

It seems original coins from the 1870-1915 period tone differently than the coins in the 1920-1930 period, and the ones after 1933 tone differently from the ones from the 1920's. Just compare the toning on a Oregon commem to a typical Alabama or Missouri.

When comparing the toning on coins from different eras, it's also important to consider advances in coin storage products.

ricko · November 22, 2009 11:54PM

And just a point of clarification for adamlaneus... "It is probably some sort of passivation of the surface, related to heat or metal movement while striking." Passivation is a chemical removal of iron ions from corrosion resistant stainless steel. A more formal definition is “the removal of exogenous iron or iron compounds from the surface of a stainless steel by means of a chemical dissolution, most
typically by a treatment with an acid solution that will remove the surface contamination but will not significantly affect the stainless steel itself.” Cheers, RickO

yellowkid · November 23, 2009 12:00AM

I enjoyed this thread, thanks all!

Can the original strike force applied during coining affect the way a coin tones years later?

Comments

Leave a Comment