Libra: YogaKaraka Saturn is also more benefic in the stars of Mercury, Moon and Saturn. In lagana when placed with Mercury and Venus it creates yoga. Neelam is very advantageous and one may always use it, irrespective of periods. Addition of Diamond or Emerald may firther potentiate benefic influences.
Scorpio and Sagittarius: In Scorpio lagna Saturn may form “Sasa Yoga” when positioned in 4th house, here one may use Neelam in the major periods of Saturn after thorough check up of chart otherwise Neelam is not suggested at all.
Capricorn: Ascendant lord Saturn also rules the 2nd house. In the star of Saturn, Mercury and Ketu it becomes yogi. It is protective charm for these natives and potentiate root of life an the whole. However, diamond should be used along with emerald.
Aquarius: Lagnesh also ruling 12th. In the star of Mercury or ketu it also becomes Yogi. One may use Neelam as a protective talisman to strengthen health, personality, prosperity and success. Mooltrikona in lagana, thus, one may use Neelam deliberately.
Pisces: Lord of 11th and 12 houses Saturn is most malefic. There is no indication of Neelam.
More about Neelam
After the trial period of 10 days one may use Blue Sapphire. Metal may be Gold(best), steel or Ashtadhatu and the best star is Pushya. Minimum weight is 4-5 Ratti and finger is 2nd. Time should be 09:00-13:00 hours and day should be Saturday falling on Anuradha,Pushya and U. Bhadra stars. Mantra to be recited is “Om Parang pareeng parong sau shanaye namah” and it should be recited 24000 times ideally. Puja should be performed with blue flowers and chandan. One should also light “oil deep” at pooja time. Fasting on the same day and recitation of Saturn “strota” is also good. Donate mustard oil, black til, iron vessels, black clothes and pulses to the servants. Inimical gemstones, Ruby, Coral and Pukhraj and they should not be worn along with Neelam.
Dedicated to the Lord of idealism “Saturn”
Reference: Gem Therapy in Vedic Astrology: Dr. Neeraj Lalwani