Why are some Carl Barks limited edition lithographs worth more than others?

Well, the simple answer is "supply and demand".

Generally, a Full-Size lithograph will be higher in higher the value and price than a Mini-lithograph because, not only is it larger, but there were fewer Full-Size lithographs created.  Both sizes have Gold Plate Editions (#1-100) but the Full-Size releases generally only have #1-345 in the Regular Edition while the Mini-Size have #1-595.

Collectors also like lower numbers…..so those with numbers 10 and under (especially #1) will go for a higher price.  

In addition to the editions originally released to the public, there were a very few prints produced as Artist’s Proofs (usually 6 of these), Printer’s Proofs (usually 10 of these) and Publisher’s Proofs (usually 15 of these). In most cases they look just like the Gold Plate Editions…..except for the numbering. However, because they are so limited in quantity, the collectability and price is much greater than the other editions.  

In order to determine the relative value of the different size, edition and numbering of the lithographs, please look over the charts below. (developed by Another Rainbow Publisher, the late Bruce Hamilton.) Just plug in a price ($xxx) for a high numbered Regular Edition and you can figure out the value of all the rest]