I have been hunting with the etrac maybe a month - just out in my yard, and maybe creeping into the neighbors just a little bit. Anyway today I found an 1858 seated liberty half dollar at about 4" next to a big rock separating the yards. Some dude probably sat on the rock once upon a time and lost it. Crisp clear high fluty signal screeming DIG ME UP. There was no iffy about this signal. Needless to say as a newbie I was very excited. The coin is in great shape. Liberty perfectly visibile on the sash, no mint mark (made in philly). It does have some black discoloration on it - and it could look a lot better if I cleaned it up - but I am afraid to. Anyone know any safe ways to clean it up or make it llok better. (Sorry - I know this type of question has problably been asked to death). Any feedback would be appreciated.