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 Replies: 114 / Views: 9,158 |
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Valued Member
 United States
108 Posts |
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Valued Member
United States
108 Posts |
The previous NYT piece, in the Olean Democrat, 1896. It was an act of congress that ordered the Philly mint to resume experiments with aluminum bronze planchets. The article states that aluminum by itself was too soft. No doubt it still softened up bronze. Tungsten would be a likely choice for hardening things up a bit. https://nyshistoricnewspapers.org/l...range&page=1Edited by philoponus6
11/17/2022 8:00 pm
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Valued Member
United States
108 Posts |
Durability of coinage was important, no doubt, and probably most important for the penny. We think of pennies as a nuisance, but in 1900 1 cent purchased what 35 cents buys now. The penny had to endure pockets, slot machines, penny pitch games, etc.
The French eventually added manganese (patent 1910, production 1920) to aluminum bronze toward that end, and successfully. .
As I mentioned earlier, tungsten-steel was showcased at the 1900 World's Fair, and was "revolutionizing engineering."
Edited by philoponus6
11/17/2022 9:04 pm
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Valued Member
United States
108 Posts |
There are some hairline scratches on the surface. The appear mostly under magnification. On the obverse they appear in the fields, both left and right of honest Abe. On the reverse there are scratches down low, near the VDB.
I am not sure the coin is cleaned, although the obverse does have a slight difference in look than the reverse. There could easily have been a change to the surface, if there were some tests for corrosiveness.
Hardness would have been a consideration if this coin is indeed an experiment. It is possible that a scratch test was performed with materials of differing hardness.
Edited by philoponus6
11/17/2022 11:05 pm
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Valued Member
United States
108 Posts |
So, it looks like Aluminum-Bronze was great for making medals. The alloy was cheap, looked almost as nice as gold, and large medals made of Aluminum-Bronze annealed much better than Copper or Bronze alone.
But, medals were not circulated. Medals were made to sit on a shelf or be hung on a wall. Circulation (both wear and corrosion, probably) was the problem with making Aluminum-Bronze cents.
On September 15th, when the first XRF on my VDB was done, I thought I had a really weird alloy, with no explanation of why such a combination of metals were used. When I started on this forum, I was still perplexed. Now, historically, it all makes sense. I am not sure about all the elements that are supposedly in the VDB, but at least the Copper, Zinc, Tin, Aluminum and Tungsten makes sense. The historical record fits the coin.
Edited by philoponus6
11/18/2022 10:11 am
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Valued Member
United States
108 Posts |
One more small fact: T1 was a form of tungsten-steel that was the first MASS PRODUCED high speed steel, beginning in 1910. Since T1 was mass produced, I presume the price of tungsten had come down to the point where it was at least foreseeable to be economically viable as an addition to coinage.
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Valued Member
United States
108 Posts |
According to one of my chemists friends, zinc is in the cent to cut down on corrosion, and aluminum would cut down on corrosion even more, but would soften up the cent quite a bit, whereby the cent would become more prone to wear. Hence, tungsten!
I wonder what else the mint tried during that era?
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Forum Dad
 United States
24154 Posts |
This topic has run it's course.  |
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Valued Member
United States
108 Posts |
On Tuesday 11/29 I took my VDB to Northeast Metal Reclaiming in WIlliamsville, NY. Their XRF did not scan well through the PCGS holder. Their more powerful one was down, and Orazio said they have been waiting for 4 months for parts.
On Thursday, 12/1, I took the VDB back, deholdered, and had him scan it raw. The results: 80% copper, 2% zinc, 2% tin and 15.5% tungsten. Orazio said definitely not gold, and the scan goes 15 microns deep - much, much deeper than ordinary plating.
Useful information: Saflips seriously confound an XRF scan.
Weight: exactly 3.11 grams.
I still haven't done a specific gravity measurement.
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Replies: 114 / Views: 9,158 |
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Posted 11/17/2022 7:33 pm
