Well, the Hijri date 12 Rabi Al Awwal 1321 corresponds to the Gregorian date Sunday, 7 June 1903. This date lies in the third month of the Hijri year 1321 AH, which is Rabi Al-Awwal of 1321 AH. Both this Hijri and Gregorian date occur on the single day that is Sunday without any doubt. The Arabic date 1321/03/12 is calculated using the Umm Al-Qura calendar and the sighting of the moon. One thing to remember is that this Arabic date may occur on different Gregorian date depending upon the region and country and obviously the moon.
If you are still not sure about the date then you can use our Arabic date converter.
The following is the conversion of the Gregorian date 7 June 1903 to its equivalent Arabic date.
The following is the conversion of the Arabic date 12 Rabi Al Awwal 1321 AH to its equivalent Gregorian date.
أَمِ ٱتَّخَذُوا۟ مِن دُونِهِۦٓ ءَالِهَةًۭ ۖ قُلْ هَاتُوا۟ بُرْهَٰنَكُمْ ۖ هَٰذَا ذِكْرُ مَن مَّعِىَ وَذِكْرُ مَن قَبْلِى ۗ بَلْ أَكْثَرُهُمْ لَا يَعْلَمُونَ ٱلْحَقَّ ۖ فَهُم مُّعْرِضُونَ
Or have they chosen other gods beside Him? say: Bring your proof (of their godhead). This is the Reminder of those with me and those before me, but most of them know not the Truth and so they are averse.
Surah Al-Anbiyaa(21:24)