Coral

Root letters:

Miim-Ra-Jiim

marjan

55:22
يَخْرُجُ مِنْهُمَا اللُّؤْلُؤُ وَالْمَرْجَانُ
Yakhruju Minhumā Al-Lu'ulu'uu Wa Al-Marjānu 

Out of both of them comes pearls and coral.

55:58
كَأَنَّهُنَّ الْيَاقُوتُ وَالْمَرْجَانُ
Ka'annahunna Al-Yāqūtu Wa Al-Marjānu 

They look like rubies and coral.