CORAL (Munga)

The ruling planet of this Gem/Stone is MARS (TUESDAY)

What you have to do:-

Donate - Donate a red coral, wheat bread, sweets made from sugar mixed with white sesamum seeds, or masoor dal ( red lentils ) to a celibate on Tuesday at noon.

Fasting - On Saturday during Saturn transits, and especially major or minor Saturn periods.

Mantra -"Aum kram krim kraum sah bhaumaya namah." To be chanted on  Tuesday, one hour after sunrise, especially during major or minor Mars  periods

This will help pleading Mars (Mangla) help in increasing your determination and drive, and pro tecting one from violence.