Is it just me?

[CU Baker]

I find myself flipping over the 1965,1966, and 1967 nicks and looking for the mint mark,knowing the whole time there is nothing there. But just can't seem to stop myself, anyone else have this lack of self control.

[henrysmedford]

Thanks for your post I just learned why no mint marks in those years. Mr. Google found this from the mints website http://www.usmint.gov/about_the_mint/collectors_corner/index.cfm?action=mint_marks

The Coinage Act of 1965


The coinage Act of 1965 prohibited the use of mint marks for a period of five years. This, together with the date freeze, eliminated distinguishing features on our coins which could tend to cause their removal from circulation during a critical period when the Mint was striving to build up coin inventories. No mint marks appear on coins dated 1965, 1966 and 1967. Congressional authorization permitted resumption of the practice in 1968, at which time the mint marks, usually positioned on the reverse of the coins prior to 1968, were permanently relocated to the obverse side.

All master dies, including those used in the Mint's numismatics and medals programs, are manufactured in the Die Manufacturing Division of the Philadelphia Mint. Mint marks are placed in the hub at Philadelphia. This hub is the tool that produces the working dies used to stamp the coins. Working dies are then delivered to the appropriate Mint facility for coinage purposes. In addition, all working dies needed for the Denver facility are produced by the Denver Die Manufacturing Division along with some of the dies for the for the United States Mint at San Francisco. Because of its secondary position in any coin designs, it has been the custom to make the mint mark as inconspicuous as possible and still be functional.

So looks like it was done to help slow down the pulling of silver coins.