The Sun is the sovereign planet of the zodiac, furnishing the light and heat upon which all life depends. The Sun's position in a person's horoscope determines his or her external appearance and public persona and provides the energy for one's personal power and influence over others. The Sun governs the fields of philosophy, government service, churches and temples, the medical profession, gold trade and public fame. Solar energy is associated with the fire element, the color red, fatherhood and masculinity, royalty and political power.
If the Sun is exalted one will be well-read, pious, strong, compassionate and untroubled. But if the position of the Sun in one's horoscope is weak or afflicted then contrary results may be expected. RED is the cosmic color transmitted by rubies and other natural red gems. Red color waves are hot and therefore useful in curing diseases caused by excessive cold and moisture in the body, viz. cold, flu, anemia, low blood pressure, heart and circulatory problems, as well as foolish behavior and learning deficiencies. In addition, Solar gemstones confer courage, eliminate sadness, moderate excess sensuality, and help elevate one's status in society.
Gemstones ruled by the Sun are natural ruby, red spinel, red garnet, rubellite and other pink or red gems with crystal clear transparency. In order to properly transmit solar energy, Sun stones must be flawless (eye-clean) and should be set in gold.