Rare (?) Plate Block #21141 Of Scott #728 - 1c Century Of Progress - Fort Dearborn

After inheriting a small plate block collection from my great grandmother, I picked up a copy of the Durland's Plate Block Catalog to help inventory the collection. I noticed several stamp issues have some PBs that catalog for higher values.

For Scott #728, plates 21141 and 21142 catalog for prices 8-10x that of the other plate numbers. I came across some PB# 21141 on ebay at a pretty low price and purchased them.

Can anyone inform me why those two PB #s have higher catalog values? I'm assuming scarcity. One resource I found online states that these two #s "were not used" and I cannot understand in what context they were not used.

Thank you for any insights ~ Pascoe

Rare? No.

Tougher? Yes. So a good find if you grabbed it as a regular 728. Better Durland Numbers are usually associated with lower print runs but are issued so I am not sure of the reference to "unissued".

Durland is pretty accurate as to scarcity. That said, some numbers they claim to be common are hardly that and others that are supposedely difficult are not that tough.

Bob

Thank you Bob!

What online communities, aside from this one, would you suggest advertising that I have these available for sale?

I'm specifically asking about communities interested in place blocks that would appreciate the ability to obtain this specific plate number.

Many thank for your expertise.

Mike

Scarcity is one thing, demand is another. There are HPO covers that have fewer then a handful known to exist, you can find them in the $1 box.
Don