Some sellers that have inherited a collection and have no idea of its value will sometimes buy a catalog to try and identify the stamp they have. In my opinion, if you’re looking at US stamps before 1935, you’re probably wasting your time. There are too many stamps that vary by watermark or perforation size. Without a watermark detector, a perforation gauge, or a magnifier, you’re just guessing what stamp you have. In my experience, many sellers guess wrong.
One seller once told me, “I stopped at the first picture I came to in the catalog that matched the the stamp I had.” Guess what. The collection he had contained cut out singles of Scott #948. The colors are orange and blue on Scott #948. Scott #1 and #2 are the first stamps in the catalog that look like those stamps. However, their colors are brown and black. He instantly went from about $1500 in catalog value for US #1 and #2 down to 20 cents in catalog value for #948.And his 10 copies of Scott #64 were all Scott #65.
Rather than spend a bundle of money on a new catalog, I suggest going to eBay or some other online auction and find a Scott catalog or a copy of the USPS Guide To Stamps. I wouldn’t spend more than $20 on a used copy. It will help tell you if you have older stamps or just modern stamps. It will explain the importance of condition and centering when determining the value of stamps, something that most non-collector sellers don’t understand. Do you know how many collections of used stamps mounted with adhesive tape I’ve turned away because the stamps are now all brown and greasy from the oils in the tape?
My best advice is to save your time and take it to a stamp dealer, preferably one who belongs to the APS and/or the ASDA. Let them look at the collection and tell you what it is worth. If you don’t agree, you can always take the collection to other dealers and get their appraisal too. If you go to three different dealers and they all give you a figure around $500, then your collection is worth around $500.
Most sellers aren’t interested or don’t have the time to properly identify stamps. Any attempt to do so is, in my opinion, fruitless. Because most times, the assumptions of what stamp it is are incorrect. I don’t want to sound negative about sellers who don’t understand stamps. I just don’t want them to become frustrated trying to identify stamps or spend lots of time and money in doing so, only to find out that it really didn’t help their position.