An emerald should be bought on a Wednesday when the Sun is in the northern quarter in an
ascending cycle. The gem should be bought and given to the jeweler two hours after sunrise.
The emerald in the ring should be set when Ashlesha, Jyeshtha, Revti, or Rohini nakshatra is
present - on a Wednesday, Friday, or Saturday when Virgo or Gemini is rising on the horizon.
The best time to wear the ring is two hours after sunrise.
Before wearing the ring for the first time it should be kept immersed for some time in raw cow's
milk. Then it should be washed with Ganga-water, spring water, rainwater, or water kept in a
copper pot. After it has been washed the ring should be kept in a green cloth on which a
Mercury Yantra is drawn with red sandalwood paste, roli, or saffron. An engraved yantra of
Mercury on a bronze plate or an idol of Mercury made of bronze should be placed on the green
cloth on which the yantra is drawn. The ring should be placed before the yantra engraved on a
bronze plate and flowers and incense should be offered to the yantra. The engraved yantra
and the gemstone in the ring should then be worshiped by reciting the mantra of Mercury.
Mantra
Aum Bum Budhaye Namah Aum
The mantra should be recited either 108 or 4,000 times and then one should meditate on the
gemstone as a symbol of Mercury. After meditation one should wear the ring on the little finger
or the ring finger of the right hand.
Afterwards the yantra should be wrapped in the green cloth and either donated to a priest or
kept in a shrine.