ErichPryde
··Seamasters ForeverYes, these marks were present when I bought the watch (although I didn't notice them at first as I was in a state of high excitement about my purchase) - see attached photos which I took on the day. As I said previously, they started as faint brown 'burn marks' and solidified over time into much more pronounced lines, evenly placed at the edges of the outside links.
Interesting to read that @EuroDriver has seen this on high-end knives, and @hen's theory that it might be something to do with heat in the production process seems very plausible... I'm going to email Omega this afternoon to request an update on their investigations and will let you all know if I hear anything (although I'm not holding my breath).
This sparked a memory for me: what @EuroDriver mentions, I have also seen this before but I hadn't really thought about it much. I had a shun 9" chef that seemed to develop a line exactly like this in color near the bolster, at a 45° angle to the handle. It was a lot less visible than this, but a definite gray line. No idea what caused it, although I wondered if I had left the knife in the sink at an angle overnight? Wouldn't have explained how isolated the mark was though and it is possible that it was always there, it was faint enough that I might not have noticed it. Cleaning it did not do anything to get rid of it.

