The American Gold Eagle is the renown gold coin in the US and is annually produced in four size increments: 1 oz, 1/2 oz, 1/4 oz, and 1/10 oz. When the Gold Bullion Act of 1985 was passed, the legislation demanded that there would be four weight sizes offered and two different types of coins minted. There were two conditions minted, brilliant uncirculated and proof (although the proof condition was only offered in 1 oz increments at first). The legislation also specified that the precious metals used, in the making of the American Gold Eagle, would be mined within the US.
The Certified 1 oz American Gold Eagles are coins that have undergone an authentication process by a reputable grading agency. During this process, coins are inspected using advanced technology to determine its appearance quality. A coin is then assigned a grade ranging from 1-70 (MS65 for example), and is placed in a "slabbed" holder for protection. This holder verifies the coin's condition and where the coin was graded.