by denverappraiser » Mar 19, 2019 I'm not going to read through all of this because it's not the sort of thread that I participate in but I would like to add a comment on the stain. That looks a stain from a chemical, not so much solder. Gold alloys can interact with lots of things ranging from perfumes and cleansers to the oil in your skin and things in the air. It's not usually what would be called a defect, and it can almost always be easily cleaned in a matter of seconds with the proper tools. If you haven't had a pro look at in person, have someone check it out. I would not summarily hold this against the seller of a used item.