Diamond wheel defect - safe?

[Dave J]

It looks like there is a bit of thickness there, I really don't think you have anything to worry about. As Bob said, just clean it up. With a washer either side it's going to be encased anyway.

Dave

[RayG]

+1 for safe. minus several million for putting the QC sticker over the defect

I'd be more concerned about balance, but you could always put it on an arbor and knife edges and see how it balances, then drill a few well placed holes to get the balance back.

Regards
Ray