Gems are being widely used as a popular astrological remedy as a remedial measure to counteract adverse planetary effects. Gems have their own power of attracting an individual by their brilliance and beauty. The ancient seers of India called them as ratnas (jewels) and used them to help an individual native. Though they are many gemstones lunar astrology advocates the use of 9 stones to counteract the adverse effect of planets. Consider Newton’s Law of gravitation: F=Gm1m2/r2And think whether gemstones affect an individual or not. Gemstones should be carefully selected after determining planetary positions in one chart, ascendant (lagna), planetary cycle and the moon sign. Careful selection of gem can bring about prosperity, mental peace and success. Kindly see the following table about the 9 gemstones described in the ancient Shastras (Divine Books):
 

Gem Name	Indian name	Representing planet	Activity
Ruby	Manik	Sun	Excellent for rulers, leaders, people involved in government work
Pearl	Moti	Moon	Good for mental peace, controlling anger, mood swings
Red Coral	Moonga	Mars	For strength, valour, energy and vitality
Emerald	Panna	Mercury	For mental activities. Good for accountants, business managers, scientists, doctors, public speakers and those involved in mental pursuits
Jupiter	Pukhraj	Jupiter	For spiritual thoughts, Spiritual advancements, and good luck, knowledge, academic success, gain of an upright husband
Diamond	Hira	Venus	For domestic bliss, attraction,good things of life,curing genital diseases. Good for actors and stage performers, attraction and sexual powers
Blue Sapphire	Neelam	Saturn	For countering the ill effects of Saturn. For wealth. Riddance from bad dreams. For excellent fate. Very strong stone. Shows its +ve or -ve effect in 3 seconds,3 minutes,3 hours or 3 days. Should be worn with caution after proper consultation.
(orange) Zircon	Gomedh	Dragon's node	Good for mental balance, stablity. Excellent for people involved in any kind of political activity
Cat's eye	Lehsunia	Dragon's antinode	For counteracting the adverse effects of ketu. For occult advancement

This is the basic introduction about the effects of gems. The Most important thing is to ascertain which is the gem that will bring about maximum benefit to an individual. All things are made up of matter so are gems. It is most important to identify which gemstone will suit an individual’s physiological and mental makeup. Gemstones such as  Blue Sapphire and Cat’s eye are so strong that  if not chosen carefully can actually act negatively and bring about the downfall of a person.

Choosing the right gem:
There are various methods for choosing the right gemstone. The question that arises is should a gemstone be selected of the planet placed favorably in an individual’s chart or the other way round. The best way is to identify the key planets that will control an individual’s life and then see their positions in the chart. If they are favorably placed one should wear the gemstone of that planet. Planets that are unfavorably placed are best pacified by chanting their mantras and stotras (prayers) and donating articles represented by that planet. For example if Saturn is badly placed in  a chart or is the lord of inauspicious houses it is best to pacify him by donating oil ,chanting the Shani stotra and chanting his mantra.

Some important points:
1) Whenever you decide to wear a gemstone be sure that you use the right metal to get it set in the ring. 

2) Wear the gemstone in the correct finger. For example Yellow Sapphire should be worn in the first finger only.Details will be given in a separate article.

Guruji Shrii Arnav - Vedic Guru is also an internationally acclaimed planetary gemmologist. An Accredited Jewelry Professional from the Gemmological Institute of America at present he is the chief mentor of http://www.astromandir.com and http://www.gemstoneuniverse.com. He is also the chief Horoscope columnist of Deccan Herald - A leading Indian English daily.