Is deception involving artificially darkening a slave's hair a valid ground for rescinding the sale?

Chapter on Selling the Musarrah (Animal with milk retained in udder)

Al-Mughni

Book of Sales

Book 12 · Issue 2 · Bab 5

Open in Qurani

Primary text

The option to rescind the sale is valid because darkening the hair constitutes deception regarding something that affects the price. This action is analogous to darkening the fingertips of a male slave if the intent of fraud is established.

Supporting text

The perceived deception from darkening a slave's fingertips is not sufficient to void the sale because it is not exclusive to indicating scribal ability; it might result from accidental contact with ink or merely being a young attendant to a scribe. This level of mere conjecture does not justify rescission.