USA 1865-66 3c Washington Stamp Priced At £100 Why?

USA 1865-66 3c Washington stamp priced at £100 by ex dealer why? I am just asking in case this stamp is worth something, is it one of the better ones or cheaper stamps? If its cheaper why did the previous dealer put a £100 price on it? Can anyone id the stamp and value? Thanks for the help

Because anyone can ask any price they want for something. Doesn't mean it will sell for that, postmark looks like 1866 ? Looks like a #65 and I see no sign of a grill.

Value maybe about 10 bucks then I suppose, some dealers do try crazy prices I just wondered why he'd try so high for a common stamp on cover like this one.

not surprising it was an EX dealer

Yeh I bought a pile of them and they all had such pricing I think it was his unsold stuff don't worry I got them cheap

Is the price written in pencil in the bottom right corner? It looks like 1.00 Pound, rather than 100 pounds.

The addressee was a New York Congressman.

https://en.wikipedia.org/wiki/John_H._Boyd

Is there any evidence that the writer was important?

How about the purple or purplish target cancel on the stamp, and some kind of residual blue markings on the perfs at right? It appears that the stamp may have been cancelled before being attached to the envelope and then cancelled again with the black target and sent on its way.
the purple absolutely does not appear to tie the stamp to the cover. All that said, it still does not appear to be a pricey item. Any further thoughts?

The cancel is black only. The purple regions in the second image appear to be false color artifacts created by image processing software that was used to (badly) enlarge a portion of the scan of the whole cover. If you click on the first image to enlarge it, then use the scroll bars to expose the cancel, it looks all black as originally scanned.