why is there such a price difference between the gold proof eagles and the unc. bullion coins, cnc is selling gold prrof eagles with box for 2,200 vs 1212 for the unc. gold eagle, tempted to sell these coins ii bought in 1986 for $800
http://www.goldcoinsgain.com/gold-ira-and-gold-401k-accounts.html Some pretty good information here. As for the difference between proof vs. bullion the more limited proof mintages classify proof eagles as collectibles where the bullion ms coins are not as rare and within the "letter" of the law potentially subject to recall much as happened in 1933. Personally, I think in practice the potential confiscation difference is not realistic but enough folks interpret legal wording in legislation to a fine degree and thus the difference currently.
I believe the gold proofs, with certificates, can be used as investments in IRAs and thus command a far more than bullion value.