How Can You Tell If These Stamp Are Rare?

I'm not a stamp collector but I acquired these stamps below plus many more 17 years ago. I don't know anything about stamps collecting. So here are a few. I appreciate any help.

There are many subtle varieties which require an understanding of characteristics like perforation gauge, printing type, and watermarks. To learn these, it requires some study. A good place to start would be on Stamp Smarter website. Alternatively, you can buy/locate a stamp with the same information.
http://stampsmarter.com/1847usa/1847Home.html


Please keep in mind that the common varieties are what the vast majority of people run across. These were produced in the billions (no exaggeration); rare varieties are rare. Unfortunately wishful thinking and 'treasure hunting' often drives some folks to incorrect assumptions and they mount the stamps misidentified. Family member and other come along behind them and then have their hopes dashed when you eventually find that do not have any rare stamps. We see this here in the community virtually every week.
Don

Rare stamps are exactly that ... RARE! Consider your odds for winning a major lottery. Then assume that the odds for your finding a rare stamp are less than even this miniscule number. I say your odds are LESS because eventually someone must win a lottery. But, for a given rare stamp, a new unknown copy may NEVER be found. Of course, that said, the improbable does happen ... albeit rarely.

General rule of thumb for evaluating the typical collection/accumulation is to assume that all stamps are common until proven otherwise and very, very, very few are even proven otherwise.