Gems are used in Eastern astrology to avert the negative influence of various planets or to increase their positive effects. The use of gems has been mentioned in the Vedic literature—the Brihat Samhita, Bhava Prakash, Ayurveda Prakash, Guruda Purana and the Rasa Ratna Samuchaya. The gem therapy described in this book is based on the Vedic (Indian) or sidereal system of astrology. Each sign of the zodiac is ruled by a planet, and each planet gives off a cosmic vibration and rules, or is related to, certain gemstones. The gems absorb or reflect the planets’ vibration, or rays. Wearing the proper gem can increase a planet’s positive effect on the wearer because the gem acts as a filter that allows only positive vibrations to have influence. Gems surround their wearer with an electromagnetic field. If a person is receiving a planet’s negative rays, wearing the correct gemstone can counteract those bad effects and allow only the planet’s positive effects to work on the person. Wearing a gemstone to counteract the malefic effects of a planet is like carrying an umbrella to avoid getting wet; the gemstone actually deflects a planet’s negative rays. It is important to note, however, that wearing the wrong gemstone can have a negative effect on the wearer. Wearing the wrong gems short-circuits the subtle body’s energy fields. Thus physical or mental problems may result. Great care should be taking when using a gemstone of a naturally malefic planet to counter act its bad effects, as instead, it may increase the bad effects of the malefic planet. To have maximum effect, the gemstone chosen should be of good quality. The better the gem’s quality, the more powerful its effect. Do not wear cracked or chipped gems, as they can have a very detrimental effect. Thoroughly inspect gems for defects before purchasing them. The gem’s size is also important. It is best that a precious stone be at least one carat; two or more carats are better. The minimum size for gems is determined by the type of gem. The less valuable the gem, the larger the stone should be to have the full effect. It is sometimes not advised to wear gems that magnify the strength of planets already benefic to the wearer. The gem may make the planet’s effect more powerful than the wearer can bear. When choosing to wear a gemstone, it is important to consider one’s overall astrological chart and to understand the synergy between the various planets. It is best to have a qualified astrologer prescribe the gem. Sometimes more than one gem will be prescribed. Gems sometimes have more effect when worn on one day than on another. To receive a gemstone’s effect, the gem must actually be worn; simply owning it is not enough. Astrological Remedial Measures Gems help to improve the effects planets have on us. To counter the malefic effects of a planet, one can also chant planetary mantras, perform sacrifices and worship, and give charity along with wearing the gem. These other activities also increase the gemstone’s effect. In general, gemstones should be worn to strengthen weak planets as calculated by the astrological chart. It is best to strengthen benefic planets when they are weak. Care should be taken when attempting to strengthen naturally malefic planets, such as Saturn and Ketu, and gems used for this purpose should definitely be prescribed by a qualified astrologer.
Eastern Gemology

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