Atlanta Gold and Coin Buyers is currently s elling a. Lot of (2) 1983 & 1986 BU Mexico Mexican Silver Libertads Onzas w/ Monster Rainbow Toning. The pictures don’t do these coins justice. Rated Best Coin Dealer in Atlanta for the past three years By Kudzu. We place a strong emphasis on personalized customer service and go above and beyond to make sure that you’re satisfied.