Sharp Edges On $1 Coin.

I've been looking through all my old commemoratives just having aich closer look at them. I've got a really shiny gold $1 coin, 1988 with the aboriginal type kangaroo on the reverse.
When I picked it up, the ridges on the edge felt sharp. But only on one set at the 1 o'clock position.

I had to go to a store today to buy some album pages (so my coins stop being in a box) and I showed it to the man there and he said it was a production error, but could not figure out exactly how it had happened.

Does anybody have any idea?
I'm going to try and get photos, but it will be hard as all I have is my phone. I'm going to get my son's USB microscope and see if that will do the trick.