Minting errors?

I have 2 Canadian coins with an abnormal halo or ring. Are these minting errors? or what could they be caused by?

I attach a photo of both coins. Oddly these are both from the 1967 Centennial series.

And does this devalue the coins or increase the value?

I would be grateful for any thoughts and advice.

Hello and welcome to Numista!

That's known as the “ring of death.” It's caused by an automatic coin rolling machine when it closes off the two ends. Like any post mint damage it lowers the value.

Oh sad. Thank you for your advice.

: )

I have some quarters like ,are they possibly worth some kindness of money?

If they're US quarters they are still worth 25 cents minimum. If there are something special about your quarters (other than the circular damage) let us know what and we may be able to advise you.