It’s a bit unfortunate that this gorgeous pipe ended up as a Grade A4, but there is some unevenness at the rim. Either it left the factory with one side of the chamber slightly thinner than the other, or — more likely — it was over-reamed a bit by a previous owner.

That said, it remains a very beautiful pipe. The issue is purely visual and does not affect the structure or the smoking performance in any way. I decided to leave it as-is rather than remove more material unnecessarily.