I have a new rule to share with you. It’s my 90-10 rule. It goes something like this, “90% of the value in a stamp collection is in 10% of the material.” My numbers may exaggerate the situation, but it is true that many times, most of the value in a collection is in a handful of items.

Sometimes when I review a collection for a seller, they don’t initially take my offer. When they call me back later to conclude the deal, I don’t have to review the whole collection again. I make notes of the best material in the collection and if that material is there on the second review, the deal can be concluded. Did the seller remove anything of value? If the key items are there, or if anything was removed, it changes the value very little. Honestly, I’m focusing on the best parts of the collection and how quickly I can buy and sell them. The lesser value material isn’t of a major concern to me.

Sellers are sometimes puzzled when dealers don’t review every single stamp in a collection. It isn’t necessary. Dealers find the better parts of the collection. That’s where the majority of the value is at. The shoeboxes of disorganized covers and the stock pages with mint stamps (read: discount postage in most cases) are quickly estimated.

There are a few collectors who assemble fabulous collections worth many, many thousands of dollars or millions of dollars and every single item is valuable. There are very few collections like that and I’ll probably never be involved in buying a collection like that. Most of the collections I see are the typical collection and if there is any value to the collection at all – it’s usually in the 90-10 category.