crimped coins

[Johnny5]

Just went thru two boxes. I got 1 1964 and two 405 silver coins. I noticed that there were a lot of nice coins (some nifc) that were in great condition except they had crimping on the edges , Does any one know if this was done intentionally or by machine error. Half the boxes seem to have this error, sample below.Damage is at the bottom of the coins.

 

[enamel7]

My understanding is that is caused by the collar clashing with the obverse die, in this case.

 

[Johnny5]

Is this considered a defect? If so is the value small?

 

[trdking]

No added value. I would guess that the event of the volume of this error would make perfect coins more desirable