The reason to correlate gemstones with astrological locations is that since everything is energy and everything is interrelated, the correspondence between gems, signs and planets can be done by looking at the properties (e.g. hardness, color, mineral families, crystal systems, chemical elements, etc. and inclusions) and other things, including mythology.
In the Vedic system, each planet has only one primary gem, although some authors consider it to be secondary gems. In all cases in the Vedic system, the gems must be as perfect as possible and color is an extremely important factor. The main stone correlations in Vedic astrology come from antiquity, and authorities generally agree on primary and secondary stones. In the Western system, confusion arises again, partly from subjectivity (for example, what is "red" for one person may be "blackish red" or "purple red" for another); partly because while the sign and gem correlations are similar, they do not necessarily add up to 100%; and because western astrologers feel that even inclusions and flaws have meaning, and therefore no two gemstones are exactly alike.
Therefore, Western astrologers subscribe to the philosophy that just as one does not find a person who is, for example, purely energy of Cancer, neither does one find too many precious stones that participate "purely" of a planet. For example, while one may be content to call a particular stone agate, agates can have a variety of colors and can be banded, layered, or single-colored. Also, agates are a form of chalcedony, which is part of the quartz family. Also, agate nodules, like geodes, can contain opal, quartz crystal, or calcite, among other things.
Vedic astrologers do not work with signs per se. His approach is more purist than that of Western astrology.
The western astrologer will use sign correlations to "combine" the planet-sign combinations and will differentiate, for example,
Venus in Sagittarius and Venus in Pisces, in addition to taking into account the positions and aspects of the house. Both Vedic and Western astrologers who are trained to work with gems can, through the premise that everything is energy, suggest certain stones to enhance, balance, or redirect certain energies symbolized by planets or natal transits. However, contrary to some magic systems, astrologers do not believe that a gem can be used to create a potential that is not inherently present in the birth chart. Nor can a precious stone be used to protect oneself from the consequences of one's actions. However, they can be used to increase awareness of the possible consequences, so they may act as a discouragement to take inappropriate action.
Where Western astrologers will work with any planet of the client's choice according to the client's birth chart, progressions, and natal transits, the astrologer Vendic works according to certain strict criteria to obtain a specific stone, which may change from time to time from time to time according to changes in dasas (planetary periods) and transits. For example, the Vedic astrologer will first look at the ascendant. If the ruler is in an auspicious sign, then the gem of choice is likely to be that of the ruler of the ascendant. Next, the
Moon sign and that sign's rule are considered, along with the naksatra (lunar mansion) rule. Planets in government and exaltation are also considered as their gemstones can also be used to their advantage according to the Vedic system.
When Vedic astrologers warn that using an unfavorable stone can cause disgrace, Western astrologers are more inclined to say, "If you like it, use it, as it is saying something about you right now."
This does not mean that they do not take into account the inherent symbolism, but that they attach great importance to free will and the client's level of consciousness. So when western astrologers select the appropriate gem class for clients' concerns, they will encourage them to select the gem themselves, the theory is that clients will choose a stone that has color correlations or inclusions or even defects that have a personal meaning. This runs counter to Vedic astrology where the astrologer "prescribes" the gem, the color, and even the specific weight and will select and set the gem for the client or send it to a specialist who will "fill the prescription." For the Client Client preference is generally of minimal importance in the Vedic system. There are also specific contraindications in terms
Gemstones for Life, Health and Progress
Power of Gemstone
