1936 Mercury Dime - Proof Vs Mint State Difference

1936 is the only year that has two different types of finishes made for proof. The common Brilliant Finish and the uncommon Satin Finish.

And there are some that's having "less than brilliant finish" that falls in between. These type and the Satin finish have extreme highpoint detail lacking in the common Brilliant Finish which were used for the rest of the proofs that follows.

There are few Satin Finish that survived being they were probably cleaned at one point, so in general those are the ones that's being the most wanted.

When I first started collecting coins I had the same problem as you are experiencing. To make matters worse I didn't even know what mint state meant! I did know what proofs were and I have no idea as to how I knew that. It just takes time, a lot of study and hands on knowledge in order to tell the differences between the two. It can be very tricky at times just like you said regarding mint state vs. proof. Usually proofs are very well struck and the devices are very sharp. Also look at the fields and look for mirror quality. Of course to make things more confusing there are coins that are called deep mirror proof like, deep proof like, semi-proof like and proof like. These coins are among the first to be struck when the dies are highly polished, thus creating a proof looking coin. As the dies wear the proof like strikes go away and thus you get mint state strikes. I still have trouble with some coins distinguishing between mint state vs. proof but it has become much easier the more I study and look at coins, so don't feel like the Lone Ranger on this!