I just bought a stripped antique mahogany desk from craigslist. The sides of the desk have dark rings where it got wet in the garage it was kept in for years.
These are not white rings in a varnish or finish. It appears more that it was first stripped, then the water caused some of the stain to come out and form a dark ring where it got wet(?).
I tried rubbing it with denatured alcohol but it is still there. Thought I would ask for any other thoughts before I reapplied some stripper to the desk.