In the Name of Allah, most Compassionate, most Merciful

The only two evidences from Islam ordering the women to cover start as follows:

Quran 24:31. "And tell the believing women to lower their gaze, and protect their private parts and not to show off their adornment except only that which is apparent, and to draw their veils all over Juyubihinna...."

Quran 33:59. "O Prophet! Tell your wives and your daughters and the women of the believers to draw their cloaks all over their bodies. That will be better, that they should be known (as free respectable women) so as not to be annoyed. And Allah is Ever Oft­Forgiving, Most Merciful."

So where is covering the face for the Prophet's (p.b.u.h) Wives "only" coming from?  Not from Allah! But a lie from the devil scholars and their devil followers.  Same reasoning apply for those who say that covering the face is for beautiful women only etc.  Covering the face is implied from the above ayahs and is for every free believing woman.  Note that from hadith and tafsir that slave Muslim women were not allowed to cover their faces.