Anything special with this 2021 quarter? Possible Planchet Error?

Kliao

Wanted to ask for some opinions on this quarter before I throw it back into circulation. Is it damage or an error? The obverse looks completely normal while the reverse is very dark grey, almost black. Although, it still does have full luster on the reverse. Any ideas? Thanks guys!

Onastone

That looks really cool, almost like a wood-grain. Don't think it's damaged...somehow came out of the mint this way...looking closely at the obverse, you can see a slight ring near the edge- like a collar held it during a press?? I like it, think it's a keeper, but I don't have enough knowledge of the minting process to explain what happened.

erwindoc

Im going to vote for PMD but not sure what. Just looks like a dirty AU coin to me.

MsMorrisine

MsMorrisine

you need a better subject line

"Sintered Planchet Error? Other Error?"

Kliao

@Onastone said:
looking closely at the obverse, you can see a slight ring near the edge- like a collar held it during a press?? I like it, think it's a keeper, but I don't have enough knowledge of the minting process to explain what happened.

That ring on the obverse is unfortunately damage from a coin rolling machine.

MsMorrisine

is part of the rim on that side "normal colored" or is that just a bright light reflection?

Kliao

@MsMorrisine said:
you need a better subject line

"Sintered Planchet Error? Other Error?"

Yeah, kinda realized that. Thanks!

Kliao

@MsMorrisine said:
is part of the rim on that side "normal colored" or is that just a bright light reflection?

Just the reflection. My desk lamp is really bright.

Steven59

As stated before - coin wrapper machine damage on obverse. Most likely roller lines on the reverse.

EDIT: Or just stuck under a cars tire when the kid had keys to the Mom's car while she was shopping and he was trying to do burnouts in the parking lot -

IkesT

Looks like an improperly annealed planchet error. This results in a greater than usual concentration of copper at the surface, which is the cause of the discoloration. Sometimes only part of the coin is discolored, as in this case.

http://www.error-ref.com/improper-annealing/

ifthevamzarockin

I have seen that dark color on some new quarters fresh out of a box.
It appears to be something going on at the mint with production.
I'm not sure if it's sintered, improperly annealed, wash problem or something else.
It appears to be part of the coin because a dip will not remove it all.
I set several aside and have been thinking about doing a thread to get some opinions.

IkesT

"Sintered" is a term that has been commonly misapplied to improperly annealed planchets.

Thanks, @ricko !

Kliao

Really appreciate the info. Bummer that the obverse has rolling machine damage.

ifthevamzarockin

This is one I set aside.

Kliao

Interesting....
However, it doesn't look as dark as the one I have though. Here it is with the classic 'gunmetal' grey color on a silver quarter.

ifthevamzarockin

I have several different shades of them and your lighting is showing it better.

I knew if I just took a quick photo it would not show as well as yours.

ifthevamzarockin

Let's see if this is any better.
If not I will try harder next time.

Edited to add a couple more of a different coin.

Kliao

And they were pulled from new rolls? I would have thought they were just dirty and moved on. Weird things happing at the mint. Do you have any P mints?

ifthevamzarockin

All mine were pulled from new rolls and solid boxes.
I don't have any P mint.
Your photos show the color better my photos look more brown than gunmetal.
The edges are bright and not discolored.

ricko

The term 'sintered' is continuously misapplied here. It erroneously refers to the dark color of a coin. In fact, sintering has nothing to do with that. Here is information. Cheers, RickO

Sintered steel is a type of metal that has undergone a sintering process, in which powdered metal is heated below its melting point until the particles form a molecular bond. Metals such as iron, copper, and aluminum are commonly turned into sintered steel. Sintered steels normally possess resistance to high temperature and slow deformation rate.