The effects gems will have depends on the nature of their Planet lord's attitude or placement in each individual horoscope. There are two types of planets in every horoscope, viz., ANUKUL-GRAHA or favorable planets, and PRATIKUL-GRAHA or unfavorable planets. Gems will act accordingly. Below are simple basic guidelines on how fine quality jyotish gems might influence us.

NOTE: SIGNS given here refer to your Thai Moon Rasi (That is the Rasi in which the Moon is placed in your Thai or Sidereal horoscope)

1. ARIES ruled by MARS: - Gems: Red Coral / carnelian

If Mars is well placed in your horoscope:
The influence will be toward positive energy, strength, courage, passion, and aggression. One will be active, have great energy, be learned, well-known and regal.

If Mars is ill-placed in your horoscope:
The influence will be toward anger, irritability, instability, impatience, and aggression. One becomes prone to violence and physical problems such as high blood pressure, anemia, and impurities in the blood.

2. TAURUS is ruled by VENUS: - Gems: Diamond / quartz

If Venus is well placed in your horoscope:
The influence will be toward attractiveness, grace, elegance, and longevity. One will be refined, humanitarian, and possess many positive qualities.

If Venus is ill-placed in your horoscope:
The influence will be toward vanity, lewdness, sensual corruption, and lack of both taste and refinement. One becomes vulnerable to loss of libido, impotence, sterility, and premature aging.

3. GEMINI is ruled by MERCURY: - Gems: Emerald / tsavorite

If Mercury is well placed in your horoscope:
The influence will be toward rationality, wit, skillfulness, and dexterity. One will be educated, happy, fortunate, and highly respected.

If Mercury is ill placed in your horoscope:
The influence will be toward aloofness, difficulty with communication, lack of concentration, and slowness. One becomes prone to speech and hearing impediments, deceptive behavior, and lack of vitality.

4. CANCER is ruled by MOON: - Gems: Pearl (natural) / moonstone
If Moon is well placed in your horoscope:
The influence will be toward sensitivity, good habits, stability, and health. One will be wealthy, industrious, and respected.

If Moon is ill placed in your horoscope:
The influence will be toward overreaction and depression. One will be hypersensitive to stress, and negative results may be expected.

5. LEO is ruled by SUN: - Gems: Ruby / red spinel

If Sun is well placed in your horoscope:
The influence will be toward nobility, dignity, power, leadership, and confidence. One will be well-read, pious, strong, compassionate, and untroubled.

If Sun is ill placed in your horoscope:
The influence will be toward lack of confidence, low self esteem, and little energy. One will be rebellious by nature, and negative results may be expected.

6. VIRGO is ruled by MERCURY: - Gems: Emerald / tsavorite

If Mercury is well placed in your horoscope:
The influence will be toward rationality, wit, skillfulness, and dexterity. One will be educated, happy, fortunate, and highly respected.

If Mercury is ill placed in your horoscope:
The influence will be toward aloofness, difficulty with communication, lack of concentration, and slowness. One becomes prone to speech and hearing impediments, deceptive behavior, and lack of vitality.

7. LIBRA is ruled by VENUS: - Gems: Diamond / quartz

If Venus is well placed in your horoscope:
The influence will be toward attractiveness, grace, elegance, and longevity. One will be refined, humanitarian, and possess many positive qualities.

If Venus is ill-placed in your horoscope:
The influence will be toward vanity, lewdness, sensual corruption, and lack of both taste and refinement. One becomes vulnerable to loss of libido, impotence, sterility, and premature aging.

8. SCORPIO is ruled by MARS: - Gems: Gems: Red Coral / carnelian

If Mars is well placed in your horoscope:
The influence will be toward positive energy, strength, courage, passion, and aggression. One will be active, have great energy, be learned, well-known and regal.

If Mars is ill-placed in your horoscope:
The influence will be toward anger, irritability, instability, impatience, and aggression. One becomes prone to violence and physical problems such as high blood pressure, anemia, and impurities in the blood.

9. SAGITTARIUS is ruled by Jupiter: - Gems: Yellow Sapphire / yellow topaz

If Jupiter is well placed in your horoscope:
The influence will be toward humanitarianism, spiritualism, optimism, faith, and good judgment. One will be powerful, respected, and a leader of men, although susceptible to anger.

If Jupiter is ill-placed in your horoscope:
The influence will be toward greed, pessimism, egotism, and selfishness. One will be uncaring, unhappy, and have a negative outlook.

10. CAPRICORN is ruled by SATURN: - Gems: Blue Sapphire / indicolite (blue tourmaline)

If Saturn is well placed in your horoscope:
The influence will be toward discipline, responsibility, realism, durability, and humility. One will be long-lived, charitable, proficient, and an affectionate mate.

If Saturn is ill placed in your horoscope:
The influence will be toward depression, anxiety, fear, loneliness, and disappointment. One becomes vulnerable to headaches, neuralgia, and other disorders of the nervous system.

11. AQUARIUS is ruled by SATURN: - Gems: Blue Sapphire / indicolite (blue tourmaline)

If Saturn is well placed in your horoscope:
The influence will be toward discipline, responsibility, realism, durability, and humility. One will be long-lived, charitable, proficient, and an affectionate mate.

If Saturn is ill placed in your horoscope:
The influence will be toward depression, anxiety, fear, loneliness, and disappointment. One becomes vulnerable to headaches, neuralgia, and other disorders of the nervous system.

12. PISCES is ruled by JUPITER: - Gems: Yellow Sapphire / yellow topaz

If Jupiter is well placed in your horoscope:
The influence will be toward humanitarianism, spiritualism, optimism, faith, and good judgment. One will be powerful, respected, and a leader of men, although susceptible to anger.

If Jupiter is ill-placed in your horoscope:
The influence will be toward greed, pessimism, egotism, and selfishness. One will be uncaring, unhappy, and have a negative outlook.

IMPORTANT NOTE: Rahu & Ketu do not rule any Rasi. But it is known that Rahu is exalted in Taurus, and Ketu is exalted in Scorpio. This meansÉ

RAHU is exalted in TAURUS: Ð Gem: Hessonite / orange zircon

If Rahu is well placed in your horoscope:
The influence will be toward originality, inspiration, insight, and uniqueness. One will be exotic, wealthy and fortunate.

If Rahu is ill placed in your horoscope:
The influence will be toward mental disease, addiction, illusion, and trouble. One will have a volatile nature, and a tendency to suffer from fear and suicidal impulses.

KETU is exalted in SCORPIO: - Gems: Chrysoberyl Cat's Eye / fibrolite

If Ketu is well placed in your horoscope:
The influence will be toward spiritualism, intuition, universality, subtleness, and sensitivity. One will be wealthy and protected from evil.

If Ketu is ill placed in your horoscope:
The influence will be toward eccentricity, explosiveness, fanaticism, and emotional problems. One becomes prone to compulsive gambling and fatal diseases such as cancer.

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