When you don't organize/document your collection...

OK, I bought a medium lot containing several dealer books of Hong Kong stamps & S/S's -- surely well-documented & priced, right? After all, everything is in dealer pages with Scott#, condition, catalog value or net value... written.

Dealer actually wrote "black print" on 2 of the pages. Black prints are complete or partial printings of a multiple colored stamp, except in black ink (or grayscale).

One was priced, modest premium, by itself on its own dealer page. Another dealer page indicated "includes black print", but the black print was actually hidden behind the normal S/S and not priced (price written is for normal S/S). Turns out, that black print is one of the early premium Hong Kong black prints. Below, the normal S/S is shown first, followed by the black print.


Scott Hong Kong #605(25Aug1991), Hong Kong Post Office, 150th anniversary.
2018 Scott catalog mint = $15


Scott Hong Kong #605v(25Aug1991), Hong Kong Post Office, 150th anniversary.
2018 Scott unlisted
2004 Yang Hong Kong catalog for 150th Anniversary Commemorative Album (book contains 23 complete mint sets and black print) = HK$1500 (~US$192 in 2004)
-- black print is item of value from album
-- recent typical sold price of black print alone is US$100-$150

For additional examples, check out the Stamp Bears thread Black Prints.