Info. from JR Society on 1795 silver

logger7

I apologize if someone else posted on this; got this information from the JR society:

David Finkelstein wrote:
During the JRCS Meeting at the 2018 Summer ANA, David Finkelstein and Christopher Pilliod reviewed Phase 1 of their research project that focused on performing chemical analyses on 1794 and 1795 dated U. S. copper and silver coins. Based on preliminary analysis, it was determined that non-destructive methods were inadequate for providing the accuracy needed for any meaningful determinations. As such, a population of early half dollars were destroyed and chemical analyses were performed using X-ray Fluorescence (XRF) and Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) technologies.

Statistical analyses proved that the Mint violated the silver coin standard of the Mint and Coinage Act of April 2, 1792. Instead of targeting silver coins to the legal standard of 89.24% silver and 10.76% copper alloy, the Mint appears to have targeted the majority of 1795 dated silver coins to a standard of 90.00% silver and 10.00% copper alloy.

Since August 2018, chemical analyses of additional copper and silver coins have been performed. In addition, a third chemical analysis technology, Titration, was utilized. At the JRCS Meeting at the 2020 FUN Show, David Finkelstein and Christopher Pilliod will present Phase 2 of their research project.

Editor's note: The JRCS meeting will be Friday, January 10, 2020 from 8:30 to 9:45 AM in room W303A of the Orange County Convention Center.

ricko

Sad to hear they had to destroy these old coins....IMO the information obtained was really not worth the loss of the coins... I am, perhaps, in the minority with my opinion - and admittedly, it is a bit selfish, since I would like to have those coins in my collection Cheers, RickO

jmlanzaf

X-ray Fluorescence is non-destructive. Frankly, ICP requires almost no noticeable destruction.

I'm guessing the issue is surface enrichment of the silver in the coins requiring a more bulk analysis.

There had to be more to the story of what they were looking for. As presented, this is just a test of 18th century metallurgic accuracy. 90/10 89/11 89.24/10.76 are really just a question of tolerance.

Also, isn't the assay a MINIMUM? I doubt very much that every coin struck was intended to be exactly 89.24% silver. That is 4 significant figures in the measurement which seems excessive since no one would complain if they got an extra few milligrams of silver. Same as with the weight of the coins.

TurtleCat

@ricko said:
Sad to hear they had to destroy these old coins....IMO the information obtained was really not worth the loss of the coins... I am, perhaps, in the minority with my opinion - and admittedly, it is a bit selfish, since I would like to have those coins in my collection Cheers, RickO

I completely agree with you here.

CaptHenway

@jmlanzaf said:
X-ray Fluorescence is non-destructive. Frankly, ICP requires almost no noticeable destruction.

I'm guessing the issue is surface enrichment of the silver in the coins requiring a more bulk analysis.

There had to be more to the story of what they were looking for. As presented, this is just a test of 18th century metallurgic accuracy. 90/10 89/11 89.24/10.76 are really just a question of tolerance.

Also, isn't the assay a MINIMUM? I doubt very much that every coin struck was intended to be exactly 89.24% silver. That is 4 significant figures in the measurement which seems excessive since no one would complain if they got an extra few if milligrams of silver. Same as with the weight of the coins.

But if you put a little bit extra silver in every coin the depositor gets back a lower face value than he is entitled to, which is exactly what happened and the government got sued.

topstuf

Huh? Extra silver reduces the value?

CaptHenway

From one deposit of silver, Extra silver per coin reduces the net face value produced from the deposit.

BryceM

Interesting. I'm astonished that they were able to assay and alloy to any sort of precision in those days. They worked pretty hard at it though and it's obvious that they had a good understanding of the science behind it.

CoinPhysicist

Just curious - who actually performed the research? OP says that David Finkelstein and Christopher Pilliod reviewed the research. Who actually performed the Inductively Coupled Plasma Atomic Emission Spectroscopy?

BStrauss3

@jmlanzaf said:
Also, isn't the assay a MINIMUM? I doubt very much that every coin struck was intended to be exactly 89.24% silver. That is 4 significant figures in the measurement which seems excessive since no one would complain if they got an extra few milligrams of silver. Same as with the weight of the coins.

It's also effectively a maximum, otherwise the depositor receives less face value and being defrauded would sue (which is what happened).

If you think about it, the assay of precious metals would be an area of science that received a lot of attention given the importance & high profile of the subject matter.

Secretly debasing coinage got several governments in a lot of trouble.

Edit: drat you auto-corrupt

cardinal

All of the destruction of the half dollars was entirely a waste! The U.S. Congress already admitted the Mint had used 90% in coinage all the way back in 1798! Case closed....221 years ago!!!

shorecoll

I'm hoping everything destroyed was seriously messed up cull.

carabonnair

Here is the O-105 that was destroyed:

This is the O-109:

CaptHenway

No great loss there!

TurtleCat

Not the best of coins but could be great hole fillers for some. What’s done is done, though. I’m curious as to the greater purpose in discovering the silver amount percentage at this point is, though. Just curiosity/research?

jmlanzaf

@BStrauss3 said:

@jmlanzaf said:
Also, isn't the assay a MINIMUM? I doubt very much that every coin struck was intended to be exactly 89.24% silver. That is 4 significant figures in the measurement which seems excessive since no one would complain if they got an extra few milligrams of silver. Same as with the weight of the coins.

It's also effectively a maximum, otherwise the depositor receives less face value and being defrauded would sue (which is what happened).

If you think about it, the assay of precious metals would be an area of science that received a lot of attention given the importance & high profile of the subject matter.

Secretly debasing coinage got several governments in a lot of trouble.

Edit: drat you auto-corrupt

Except that it is a precision issue. We used to say that every digit costs a factor of 10. It might be cheaper for the Mint to give the customer an extra $ than to assay to 4 significant digits. If it costs $2 to assay, cheaper to throw in an extra dollar.

I'm not saying that the Mint or the depositor would tolerate 90 or 91 instead of 89. I'm saying that they aren't even going to notice the difference between 89.24 and 89 3 or 89 4

Its the difference between getting 894 silver dollars for Martha's silver and 893.

Would the depositor be unaware? Wouldnt he bring in X ounces of silver which was weighed at deposit and be promised X-y ounces of coined silver? Or was the payout determined only after assay and coinage by the mint?

BStrauss3

@jmlanzaf said:
Except that it is a precision issue. We used to say that every digit costs a factor of 10. It might be cheaper for the Mint to give the customer an extra $ than to assay to 4 significant digits. If it costs $2 to assay, cheaper to throw in an extra dollar.

I'm not saying that the Mint or the depositor would tolerate 90 or 91 instead of 89. I'm saying that they aren't even going to notice the difference between 89.24 and 89 3 or 89 4

True

@jmlanzaf said:
Its the difference between getting 894 silver dollars for Martha's silver and 893.

And I wish people would stop repeating garbage stories. The daybook clearly shows the deposit was Mexican silver dollars.

BStrauss3

@TurtleCat said:
Not the best of coins but could be great hole fillers for some. What’s done is done, though. I’m curious as to the greater purpose in discovering the silver amount percentage at this point is, though. Just curiosity/research?

It might be possible from the trace amounts to determine the source of the silver from the impurities...

jmlanzaf

@BStrauss3 said:

@jmlanzaf said:
Except that it is a precision issue. We used to say that every digit costs a factor of 10. It might be cheaper for the Mint to give the customer an extra $ than to assay to 4 significant digits. If it costs $2 to assay, cheaper to throw in an extra dollar.

I'm not saying that the Mint or the depositor would tolerate 90 or 91 instead of 89. I'm saying that they aren't even going to notice the difference between 89.24 and 89 3 or 89 4

True

@jmlanzaf said:
Its the difference between getting 894 silver dollars for Martha's silver and 893.

And I wish people would stop repeating garbage stories. The daybook clearly shows the deposit was Mexican silver dollars.

The reference was meant to be simply ironic.

BStrauss3

The internet is where sarcasm went to die....