Repair of label-damaged leather binding

[Eames Collection Librarian <eames.librarian@GMAIL.COM>]

Colleagues,

I have encountered a custom-made quarter-bound morocco book box, for a
very rare 19th century book, which appears to have had a spine label
affixed and removed. Particles of the green leather lifted when the
label was removed, leaving an unsightly light patch, 2x2", speckled
with green. How can I repair this regrettable and highly visible bit
of damage?

Thank you for your recommendations.

Nancy Fadis, MLS
Eames Collection of Rare Books
San Francisco Bay Area