Thanks to Rick Miller
Jaime Hernandez: The reverse of this business strike coin was struck with a reverse proof die accidentally.
There are three recognized dates for the Lincoln cent business strike cents which display a proof reverse design. These are the 1998, 1999 and 2000 Wide AM business strike cents.
The 1999 Wide AM is by far the scarcest of the three. As of 2009, this coin commands over $100 even in the lowest condition. Furthermore, thousands of examples of this variety are probably still in circulation.
The 1999 Wide AM cents can be found in mint state grades and higher with some searching. However, examples in mint sate grades will cost several hundred dollars. In grades of MS66 and higher they usually command about $1,000. Coins graded in MS67 will bring about $2,000 with MS68 graded examples bringing in about $4,000 and higher.
PCGS has graded just over 1,000 coins for this variety with the majority of them being in MS66 condition. Most examples for this variety should still be in circulation, with many of them being in the lower mint state grades and the majority of them in AU grades.
The easiest way to determine if a 1993 to 2008 business strike Lincoln cent is struck with a proof reverse die is by looking at the letters AM of AMERICA.
• From 1993 to 2008 business strike Lincoln cents should display the letters AM of AMERICA close to each other and almost touching or the Close AM style reverse. Anything different, is considered a variety or a Mint error.
• From 1994 to 2008, regular proof Lincoln cents display the letters AM of AMERICA separated from each other or the Wide AM style reverse. Anything different, is considered a variety or a Mint error.