Arguably one of the most misidentified mint mark types, the 1981 'Type 2' mint mark suffers often from zealous misidentification of its common sibling. It is quite different yet similar to the mint mark used early in the year, yet it is quite a bit less common and much less frequently correctly spotted. Only about one in 100 1981-S proof cents have this mint mark type, and no other year has the same type.
The largest distinction between this and the other type used in 1981 is that this mint mark is open from the inside loops to the field outside the mint mark, and if you were an ant you could drive your car on top of this mint mark without falling off - the relief is completely flat on its high point. Additionally, its larger head at top makes it look like it is listing to the right, just about to fall over. These are very distinct little features that will forever help you remember this scarce little mint mark. Happy hunting!
