First Strike commercial coin.

Yes the blanks are heated to anneal them. THEN they are washed and dried. When they enter the coining press they are cold (room temperature) they are NOT struck while they are hot. And at the relatively low temperatures that can be achieved during the striking (possibly as much as a couple hundred degrees) no chemical change takes place. No chemical change takes place during the annealing either other than oxidation on the surface of the blanks. (which is removed through chemial and physical processes during the washing.) The softening that comes about from the annealing is a mechanical process not a chemical one. The work hardening that takes place during the rolling, blanking, and upsetting is also a mechanical process not a chemical one.

OK that's the problem a miss use of terms. Yes the heating does result in a rearranging of the molecules and the bonds between them that's a mechanical rearranging not a chemical one. Only their physical placement has changed.

 

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Conder101,
my stroke messed my head up . But that video does not remind me of what I've seen at the Denver mint back in 98.
After the blanks were punch they went to be washed the video has it the other way around. And after the blanks were rinsed, they went to the furnace to be dried anywhere from 1000° to 1650. And they were cool down to around 100° and sent to the upsetting mill then to the press,

that's the way I remember their tour in 98 not what the video showing.
Something was bothering me about your statement that I reviewed the video and said no that's all wrong. If you washed and rinsed the blanks after preheating you would defeat your purpose of softening the metal because in the's rents cycle you would change the molecules of the blank again.
Then what you gonna put it back in the furnace to dry them.

Punch wash furnace upsetting mill and press.

 

Metals such as for coinage does not have molecules until they come in contact with elements that are not metals such as sulfur, oxygen, etc. They are held by metallic bonding and form different arrangements unlike traditional covalent and ionic bonding. Here is a simplified discussion of it.
https://www.chemguide.co.uk/atoms/bonding/metallic.html

 

Thank you very much but in layman terms the composition of the metal changes.
Is that a better statement

 

The metal becomes compressed,
I am not a metallurgist, but, until you add a foreign agent, substance -the composition stays the same.

 

No, the composition doesn't change. The metal is not transmuted, so the same metal(s) in the same proportion(s) will still be there. It may have the shape changed, and a minor change in physical measurements, but the mass should be the same. And as P&G mentions, that is usually environmental chemicals such as sulfides, carbonate, chloides, etc. involved in "toning" or "corrosion" depending on how one defines such.

 

Personally, I have no idea why the coin might look like that. Maybe it was washed post mint.

What I DO see from your photo's is a coin which, while it may stand out in the crowd, it also appears to be bagged and choke full of grade limiting hits.

Not, IMO, a very god specimen.

Just my opinion.

 

Based solely upon the first image you've posted, I'd say it "appears" to have high luster due to the uneven fields. Similar, IMO, to coins which are NOT first off the dies but closer to last off the dies.



Again, just my opinion.

 

I agree with you, this coin is in bad shape.
But still it stands out among the others as indicated in the photo with the three other quarters.
The only way I would be able to prove this theory if I had the first run coinage off the press just the first 20 coins.

But we know that's not gonna happen.
So I can only go my my personal experiences with metals,
And basically you have to listen to what the coin is telling you what happened.

I know the quality of this photo is not that great. Always working on improving photographs.
USMC60
PS
I find it surprising nobody has mentioned blank oxidation including myself until now.
I think this plays a big factor in the equation. Just my opinion and something to think about.

 

Just want to throw my two cents in, one trick I learned as a mechanic.
Cold metal contracts. Heated metal expands

 

First of all these first strike coins do not end up @ the bottom of the bin as you propose. Their location in the coin bin correlates more to how full the bin is when a die is changed.

Second - blanks are fed into the coin presses through a continuous feed process that based on my knowledge has no planchet pre-heater attached.

Third when dies are changed on a coining press - the first struck coins are diverted to an auxiliary collection shoot and captured for inspection by quality control. What QC does with these coins after inspection - I have no idea.

Fourth - there are other intermittent issues in the coin manufacturing process that cause the coin press to cease production for a period of time allowing the dies to cool. And etc, ect

At this time, based on the minting process as it stands now, one cannot designate a first strike coin with a high level of assurance.

But I do agree that the Mint has the capability and could easily capture these first strike coins and assemble them into special mint sets that the general public would probably be willing to pay a giant premium for.

 

The blanks went into a furnace to be annealed, not dried. Annealing is step that increases ductility of the metal

Nearly all materials expand upon heating and contract on cooling (there are a few special cases due crystal phase changes and other funky stuff). Coefficients of Thermal Expansion for common metals are well studied. If I did my math correctly a quarter will expand (linearly) slightly less than 0.001" (1 thousandth of inch) for every 100F it is heated, and contract equally when cooled.

Hands on, personal experience and observations can be very valuable. But if you don't speak the language, then you can make some significant translation errors when listening to what the coin telling you.

I suspect that you can find some good metallurgy sites that explain ductility, work hardening, and Thermal expansion, without getting into heavy math or chemistry. If you're really interested, some of this stuff could help supplement your hands on experience

 

Still say it looks heavily plated with Platinum.

 

The blanks HAVE to be washed after annealing. (And there is no reason to wash them before annealing) The annealing is a high temperature heating (That's your 1000 to 1650 degrees). This causes oxidation scale to form on the blanks. That has to be removed. The drying is done at a MUCH lower temperature (Maybe 140 degrees tops. You are just trying to dry them, no reason to use high temperatures.) That doesn't form oxidation and is way to low to cause any softening of the metal.

I assume you mean rinse cycle. The chemicals chosen to clean the oxides off the blanks react with the oxides, not the coinage metal. Usually they also tumble them in the solution along with steel shot to burnish the surfaces and help remove the oxides by abrasion.