The Coin Look - Counterfeit Detection - 1916-D Mercury DimeThe 1916-D Mercury Dime is one of the most counterfeited/altered coins on the market.
I heard something from a coin dealer, not long ago, regarding the big silver rise of 1979-80. They stated that other melters (themselves included) estimated over 750,000 "full" sets of Mercury Dimes were bought in to be melted. Strangely enough though, there were only 264,000 made... and this was over 30 years ago! Now I will admit I do have my doubts that it was that high, but it is still an unsettling figure.
In grades Good or better, it is quite easy to discern between the good and the bad. It is the low grade that can be very tricky.
The Coin pictured below was graded F-15 by PCGS. Notice the shape of the D, the top and bottom of the letter are parallel. Also note how the inside of the D has a triangle pattern shape as illustrated.
As I mentioned before, it is the lower grades, About Good or worse, which can be difficult. The coin below was graded as a 1916-D 10c AG03 by ANACS. Many of the early dimes are worn past the rim and into the lettering/mintmark. A 1916-D Mercury Dime in this condition gives many numismatists problems.
The following coin has an altered mintmark according to NGC. The D is deformed compared to the D in the first picture. Without proper magnification, this coin would fool many people.