Professional Stamp Experts (PSE) is an organization that issues certificates of authenticity on stamps. They also offer graded certificates.
They recently published a new book, “The Philatelic Book of Secrets”. The cost is $10 and you can order it online at http://www.philatelicsecrets.com. I highly recommend this book for your philatelic library.
Yes, the book does go into some detail on how stamps are graded. What I think is more revealing to the casual collector (who may not be interested in graded stamps) is that the book also talks about repairs, reperforated stamps, regummed stamps, counterfeits, and so forth. I found the information very useful and I think you will too.
Will this book make you an expert? No. But there are tips offered that will make you more knowledgeable. And knowledge is power.
Sometimes customers will ask me, “How do you know if a stamp has been reperforated or regummed?” There are certain things I look for. This book goes into great detail about how PSE makes various determinations. Some of the techniques they use can be used by you too. That’s where I think this tool is a valuable reference to you, the typical collector who doesn’t know necessarily what to look for.
This book belongs on your philatelic bookshelf. It’s a valuable tool for you to use to protect yourself against buying items that are not what they seem to be. When in doubt, especially for very valuable items, a certificate of authenticity is your best protection.