My post was in response to new member @Joemama73 who joined yesterday, not the original author of the thread. (Welcome, BTW, @Joemama73.)
@lordmarcovan have a good explanation. Your coin was plated AFTER it left the mint. Therefore, it's not an error. In fact, the plating is actually considered damage by knowledgeable collectors, so your coin is only worth face value. The PCGS label says GENUINE, which means means it was a real coin struck by the mint. SURFACE TREATMENT means at was plated AFTER it left the mint. XF is the grade. DETAIL means the coin suffered some type of damage after it was minted (plated in this case). Sorry, but you won't find a coin like this in an auction because of the damage. However, you do have a nice remembrance of your great-grandmother, so it isn't a total loss.