Niqab is not farz. It's not even sunnah. Look up the hadith's. There is a clear hadith which outlines what exactly remains uncovered, and the face is on the list.
In the Quran, I believe its Surah Nisa, requires that you as a female communicate so that they may see your face.
As per Islam, you are required to show your face.
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this is exactly what it should be and thats what i also said.
i wudn't go that far to say that its REQUIRED TO SHOW ur face...i wud say...u MAY show ur face**