• لُؤْلُؤ

Appears 6 times in the Quran.

1. 22:23 إِنَّ ٱللَّهَ يُدْخِلُ ٱلَّذِينَ ءَامَنُوا۟ وَعَمِلُوا۟ ٱلصَّٰلِحَٰتِ جَنَّٰتٍ تَجْرِى مِن تَحْتِهَا ٱلْأَنْهَٰرُ يُحَلَّوْنَ فِيهَا مِنْ أَسَاوِرَ مِن ذَهَبٍ وَلُؤْلُؤًا وَلِبَاسُهُمْ فِيهَا حَرِيرٌ

   Surely Allah will make those who believe and do good deeds enter gardens beneath which rivers flow; they shall be adorned therein with bracelets of gold and (with) pearls, and their garments therein shall be of silk.
   

2. 35:33 جَنَّٰتُ عَدْنٍ يَدْخُلُونَهَا يُحَلَّوْنَ فِيهَا مِنْ أَسَاوِرَ مِن ذَهَبٍ وَلُؤْلُؤًا وَلِبَاسُهُمْ فِيهَا حَرِيرٌ

   Gardens of perpetuity, they shall enter therein; they shad be made to wear therein bracelets of gold and pearls, and their dress therein shall be silk.
   

3. 52:24 وَيَطُوفُ عَلَيْهِمْ غِلْمَانٌ لَّهُمْ كَأَنَّهُمْ لُؤْلُؤٌ مَّكْنُونٌ

   And round them shall go boys of theirs as if they were hidden pearls.
   

4. 55:22 يَخْرُجُ مِنْهُمَا ٱللُّؤْلُؤُ وَٱلْمَرْجَانُ

   There come forth from them pearls, both large and small.
   

5. 56:23 كَأَمْثَٰلِ ٱللُّؤْلُؤِ ٱلْمَكْنُونِ

   The like of the hidden pearls:
   

6. 76:19 وَيَطُوفُ عَلَيْهِمْ وِلْدَٰنٌ مُّخَلَّدُونَ إِذَا رَأَيْتَهُمْ حَسِبْتَهُمْ لُؤْلُؤًا مَّنثُورًا

   And round about them shall go youths never altering in age; when you see them you will think them to be scattered pearls.