What is the ruling on a Muslim woman uncovering her hair in front of a Christian woman, and is it permissible for a Muslim woman to have her hair cut by a Christian woman?

The preponderant view among scholars is that it is not permissible for a disbelieving woman to see of a Muslim woman anything but her face and hands. The reason for this prohibition is the fear that the disbelieving woman might describe her to her disbelieving husband. This is the madhhab of the Malikis, Hanafis, and Shafi'is, and one narration from the Hanbalis. Al-Qurtubi held the view that a Muslim woman must cover her entire body in the presence of a disbelieving woman, basing his opinion on the verse from Surah An-Nur: "or their women." Accordingly, it is not permissible for a Muslim woman to uncover her head in front of a disbelieving woman, whether for cutting hair or for any other reason.