This is something you see all the time on eBay. Sellers will even weigh a watch whole to give you a big number trying to sell by weight. Of course to be honest you would have to remove the movement, stem, crystal, and the springs in the case just to get down to the actual metal that has any gold in it. As far as gold content goes, I think most who buy these take a chance on how much actual gold is left in them... My opinion on how much gold is left in them; not much!!!
Raymund L. Brown
"Associate with men of good quality if you esteem your own reputation; for it is better to be alone than in bad company".