Just back from PCGS - SBA dollars on Experimental Planchets

MrEureka

I recently bought two 1999 SBA Dollars struck on experimental "golden" planchets. The coins exhibit distinctly different colors so I figured I'd test them for elemental composition.

The results:

70% Cu, 28% Zn, 2% Ni (This one is greenish gold and the coin looks like a "specimen" strike.)
73% Cu, 25% Zn, 2% Ni (This one is surprisingly close in color to the Sacagawea planchets and is not from specially prepared dies. I was a little concerned it might turn out to be a less interesting wrong-metal error struck on a regular Sacagawea planchet. Phew!)

By comparison, the adopted composition of the Sacagawea is an outer layer is 77% Cu, 4% Ni, 7% Mn, 12% Zn and a pure copper inner core. Far different from my experimental SBAs!

If anyone else out there has one of these experimental pieces, please let me know and please have the coin tested. I'd also encourage anyone owning a 1999 state quarter struck on a similar experimental planchet to have it tested as well. We have an interesting story in the works!

Rampage

Wonderful find! I wonder if Mike still has his state quarters for sale that were struck on experimentals.

MrEureka

Hmmm...

Rampage is the only one that thinks these are cool?

These are the coins the US Mint struck while trying to figure out a composition for the Sacagawea. They're transitionals in the most legitimate sense. And each is very possibly unique. To me, it doesn't get much cooler than that.

But maybe I'm deluded. Maybe they're really just "modern crap".

D

I would think they were cooler if I could see them, if that counts...

-Daniel

NumisOxide

<< <i>Rampage is the only one that thinks these are cool? >>


No, I think they sound cool. Do you have any images?

MrEureka

No, I think they sound cool. Do you have any images?

No. Fedex still has the coins. I'll shoot them next week and post images.

NumisOxide

<< <i>No, I think they sound cool. Do you have any images?>>

<<No. Fedex still has the coins. I'll shoot them next week and post images. >>



Alright, looking forward to seeing them Andy.

relayer

<< <i> Maybe they're really just "modern crap". >>

No, they are modern error crap

oreville

This is cool!

Did PCGS indicate whether the coins had a solid copper inner core or not?

sinin1

I think they are cool


how did you get them?

MrEureka

Did PCGS indicate whether the coins had a solid copper inner core or not?

No, and it does seem likely that some (if not all) experimental pieces exist with such cores. However, given that we don't know the mass of the cores, I do not know how this could be tested.

Edited to say that a specific gravity test could tell us if there's a core, but it cannot tell us if it's pure copper. On the other hand, there may be a way to X-ray the coin and determine the size of the core, which would then tell us if it's pure copper. This I leave to the next owner.

INXS

This may be able to be answered by DRG or at least he would have an interest in these.

Hre is something on them SBA.

IGWT

-- "Rampage is the only one that thinks these are cool?" --

I think that they're way cool. The problem is that pretty much everything pales by comparison to Fraser's 1911 Lincoln electrotype trial.

DHeath

No manganese and more zinc. The blanks your transition pieces were struck on would have been harder, wouldn't they, or do I have that backward? Cool discovery.

PerryHall

Are these legal to own? Sounds like the experimental cents struck on aluminum planchets in 1974. Someone must have removed them from the mint through the "back door" although I'm sure it will be claimed they were found in circulation. I also think they are cool but I would be concerned the Feds may want them back some day.

errormaven

Were several tests conducted at different voltages? This is essential for determining whether the coin is a solid alloy or a composite. It's also essential for determining whether the percent values you cite are accurate throughout, accurate at only a certain depth of penetration, or merely an average of different percentages at different depths.

Byers

<< <i>If anyone else out there has one of these experimental pieces, please let me know and please have the coin tested. I'd also encourage anyone owning a 1999 state quarter struck on a similar experimental planchet to have it tested as well. We have an interesting story in the works! >>



Hi Andy,

Your SBA Dollars on experimental planchets certified by PCGS are extremely rare with only a handful known. Below is some information, pictures and a lab report on 1999 State Quarters on experimental planchets certified by PCGS. The rarity and the wide variety of different alloys of the State Quarters and SBA Dollars indicate the experimental nature of the pieces. Clearly, there is nothing accidental about their production. This is one of the more exciting new discoveries in numismatics in recent times.











There are approximately 15 known 1999 State Quarters struck on Experimental Planchets. All five states in the 1999 series (DE, PA, CT, GA and NJ) have been discovered.
These Experimental State Quarters have sold for as high as $10,000 each, depending on which state, the coin's condition and which type of experimental composition was used.

There are four known types of experimental compositions which have been discovered so far on 1999 State Quarters.

Type #1 - This type has the "color" of a Sacagawea Dollar and has the copper center core.
Type #2 - This type has the "color" of the Sacagawea Dollar but does not have the copper center core.
Type #3 - This type has a slight "green" color and has the copper center core.
Type #4 - This type has a slight "green" color but does not have the copper center core.

Here are a few "telltale" signs to determine if you have discovered a State Quarter on an EXPERIMENTAL PLANCHET in circulation:

WEIGHT - The weight on ALL of these discovered so far is OVERWEIGHT - varying from 5.9 grams to 6.3 grams.
SIZE - It is slightly THICKER than a regular State Quarter, due to the heavier planchet.
COLOR - So far, the pieces discovered are either the same "color" of the Sacagawea Dollar, or have a slight "green hue" to them.
LOOK - The edge is slightly rough and may have a higher rim around part of the edge.
EDGE - Some of these do NOT have the center COPPER CORE.
STRIKE - None discovered so far are proof-like in the fields.
REEDING - Some of these have incomplete reeding.

These coins were analyzed by spectroscopy (SEM-EDX) using electron microscopy and energy-dispersive x-rays to determine the alloy composition. The predominant metal is copper, followed by zinc. There are also small percentages of manganese and nickel. PCGS and NGC have both authenticated and certified these 1999 State Quarters as being struck on experimental planchets.

A Freedom of Information Act (FOIA) request for copies of any reports and test results was submitted to the Department of the Treasury. They acknowledged that “the U.S. Mint conducted engineering and metallurgical tests as part of its development of an alloy for the Golden Dollar”, but would not release any information.





This discovery was featured on the front page of Coin World and also on their online version. Click here for the article.

Outhaul

Hey Andy...

Gemineye

Good info on the subject of the SBA...........

CoinHusker

<< <i>
Hre is something on them SBA. >>




Thanks for the link INXS Very and very interesting.