I searched but I couldn't find this topic so here goes.
A rather large lot of these came with a collection I purchased. I know nothing about this collecting specialty so I'm not sure how to value them for trading or selling. I'd like to see them go to someone who can appreciate all the time and effort someone put into identifying all those flyspeck differences.
The collection includes several hand-written and typed lists of varieties. There are over 150 different types and there are examples of most of the numbers on the stock cards.
I tried contacting members of the US Stationery specialty group, but didn't receive any responses. Does anyone here have a bit of knowledge about this very specialized collection?