1952 Shilling with a flake? through some denticles

[ttkoo]

On the reverse of this grubby 1952 Shilling, there is a 'flake' running from the rim and appears to go through some denticles adjacent to the LH star, (obviously it is not piercing through).
I'm struggling to get my head around what caused it. An inclusion, a die crack, a strike through. I'm hoping one of the brains trust here will immediately know what it is and let me know.

Thanks in advance

ttkoo

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[echidna]

My guess is an offset die clash.

[Basilstate]

I'm not sure,first thought was foreign material but the star has something going on as well.

[ttkoo]

I think the star is 'normal' in hand. Some crud has washed off in an acetone rinse and exposed the patina below. Foreign material could be it. I can't help but think I have seen similar before on a florin. I'll have to have a dig through the treasure chest and see if I can locate it.
Hey, thanks for the input.