coin double rims

carl

I've heard and seen lots of stories, articles, pictures, etc of double die coins but never a mention of double die coin rims. I've been collecting for about fourty years and have saved numerous coins that show a double rim. They are very common with the 80's Lincoln Cents. Any one else know anything about them?

JRocco

Do you mean collar clashes like these examples?

carl

That's exactly what I mean. Just wondering how common they are?
Any value to them? What causes them? Why are they not mentioned in any coin books? I have so many of them I was thinking about just taking them to a bank for the cash.

ibzman350

I have always wonder what was going on with this morgan.





Herb

joeyuk

Is this the same thing?

JRocco

These are fairly common Carl. They are the result of a die that got damaged by hitting the interior edge of the collar and that outline got transferred to the die. They don't have much of a premium, but a lot of minor mint errors do not. I do keep them though (like I keep everything else) and have a few tubes of them put aside. I find they are most common on dimes and quarters and the variety that shows full reeding are much more interesting.

errormaven

There are at least six different causes for double rims. The three most common causes are:

1. collar clash (hammer die collides with top and/or scrapes along working face of collar.
2. slight horizontal die misalignment
3. "finning" of the rim due to excessive overall striking pressure or excessive localized striking pressure caused by minor die tilt.

The first dime clearly shows collar clash, as indicated by the serrations at the top of the rim.

-- Mike Diamond

JRocco

Hi Mike. I was under the impression that coin # 1 shows "heavy collar clashing" while coin # 2 shows "collar clashing". I always thought that both types of clashing can occur on a reeded coin.

errormaven

<< <i>Hi Mike. I was under the impression that coin # 1 shows "heavy collar clashing" while coin # 2 shows "collar clashing". I always thought that both types of clashing can occur on a reeded coin. >>



Collar clash is collar clash. Naturally, it occurs in varying degrees of severity.

When you've got the serrations, you know you've got collar clash. Without the serrations, it's more difficult to tell. The second dime might simply be a minor horizontal misalignment of the hammer (obverse) die. The double rim in that case would be caused by coin metal filling the rim gutter (the "inner rim") and squeezing out laterally between the die neck and the collar (the "outer rim").

Naturally, you can also get collar clash and a minor misalignment occurring together.

JRocco

Thanks for the explanation Mike.

cladking

<< <i>There are at least six different causes for double rims. The three most common causes are:

1. collar clash (hammer die collides with top and/or scrapes along working face of collar.
2. slight horizontal die misalignment
3. "finning" of the rim due to excessive overall striking pressure or excessive localized striking pressure caused by minor die tilt.

The first dime clearly shows collar clash, as indicated by the serrations at the top of the rim.

-- Mike Diamond >>



I have noticed that a lot of the double rimmed coins are misaligned but don't understand how this results in the doubling.

errormaven

<< <i>

I have noticed that a lot of the double rimmed coins are misaligned but don't understand how this results in the doubling. >>



The "inner rim" is caused by coin metal squeezing into the rim gutter of the die. That gutter creates the design rim on the finished coin. The "outer rim" is caused by coin metal squeezing past the rim gutter into the gap between the die neck and the collar.

cladking

<< <i>
The "inner rim" is caused by coin metal squeezing into the rim gutter of the die. That gutter creates the design rim on the finished coin. The "outer rim" is caused by coin metal squeezing past the rim gutter into the gap between the die neck and the collar. >>



That makes sense and seems to be especially typified in the '85-P in the first post.

Thanks for the explanation.