US 15 Cent Revenue With Missing Washington Face

Could somone clarify and identify whats going on here


Appears the face is missing or faded ?
Does it make it more collectible and valuable ?


*** Moved by Staff to a more appropriate forum. ***

Faded. Several revenue issues including the second and third issues and the first proprietary issue were printed on Willcox Chameleon Paper in fugitive inks. One ink was susceptible to acids and the other to bases; this was done to prevent cleaning and reuse at a time when pennies were still real money. Sunlight would also fade the vignettes as well. There was a time in the late 19th century when people faded the vignettes deliberately to create fake inverted centers using essays of the vignette that had been sold off as scrap.
Alas, it makes it less valuable.