In addition to precious metals investment, there is a demand for American Gold Eagles as collectibles. This may take the form of purchasing the limited mintage collectible versions of the coin produced by the US Mint. It may also take the form assembling sets of high grade PCGS and NGC Gold Eagles (Buy on eBay) for either the bullion or collector coins.
Professional Coin Grading Service (PCGS) and Numismatic Guarantee Corporation (NGC) are third party authentication and grading firms that accept submissions from coin dealers and collectors. They will verify the authenticity and evaluate each coin to determine a numeric grade. The coins will be encapsulated in a numbered holder which attests to the authenticity and indicates the grade.
Although nearly all American Gold Eagles exist in uncirculated grades, attaining perfect grades can be difficult. This is especially true for the bullion coins, which are not minted and handled with the special procedures afforded to the collectible proof and uncirculated coins. The highest grades awarded by NGC are NGC MS 70 for bullion and collectible uncirculated coins or NGC PF 70 Ultra Cameo for proof coins. The highest grades that PCGS will award are PCGS MS70 for bullion and uncirculated coins and PCGS PR70DCAM for proof coins.
Some collectors seek to assemble PCGS or NGC American Gold Eagle collections in the highest grades possible. The scope of the collection can be narrowed by focusing on bullion coins, proof coins, or collectible uncirculated coins. Collectors can also focus on a single denomination, either one-tenth ounce, one-quarter ounce, one-half ounce, or one ounce coins.