Rule # ONE
Train to tune into the cosmic clockwork. Know that nothing is isolated.
The clock is precise.
As astrologers, we are only Time Readers.
~ NJ: The Jewel Whisperer
Assessing through Multiple Systems of Astrology, simultaneously
In over two and a half decades of my experiments with astrology and gems, I have found something very interesting. For most natives or birth charts, it is not a question of finding the most suitable gem. Rather surprisingly, it is just about ruling out the ones that will not get the desired results. Ending up with three gems is rare and one has to be lucky to get to two gems, both suitable. However, in most cases, it is just one gem. THAT ONE GEM, would tune-up the entire internal cosmic mechanism of the native and will potentially do wonders with time.
Here are some simple methods one may experiment with before consulting the expert. Begin with the natal birth chart after performing proper birth time rectification (External Link: https://www.astrogle.com/astrology/birth-time-rectification-through-k-p-astrology.html), preferably using the Ruling Planets of KP (Krishnamurthy Paddhyati) System. Take the Natal Chart, find out the Nakshatra (Lunar Mansion out of the 27 Mansions) and its Charan (the assigned Phase out of four phases) and write down both the Lords of the Nakshatra and the Charan. The Charan of Nakshatra denotes the area of sky where Moon was positioned (degrees and minutes in a zodiac sign) at the time of birth of the native. Then, note the House Lords of the Ascendant (Tanu-Bhava, house of self and beginning), the Fifth (Vidya-Sthana, house of creativity and intelligence) and the Ninth (Dharma-Sthana, house of father, religion and good fortune) house. In traditional astrology, these three houses are the most important ones for finding out suitable gemstones for a birth chart, at a basic level. Note that all these houses are Fifth from one another, which essentially means intertwined, accumulated good fortune of past incarnations (look up Vedic astrology fifth house: External Link: http://www.barbarapijan.com/bpa/Bhava/5putra_bhava.htm). The Ascendant and Nakshatra – Phase may vary with slight changes in time so before recording the astrologer should crosscheck these. Some techniques include using the characteristics of Nakshatra to ascertain whether the personality traits of the native match and using the Ascendant sign to match and verify with the Ayurvedic Prakriti (Physical constitution / natural imbalance or disorders).
After recording all five planets of lordships as instructed above, find out which ones of these have absolutely no connection with the Dussthanas (negative houses) Sixth, Eighth and Twelfth houses. The connection could be with the rulers of these houses, the Dispositors (the planets which are the rulers of the sign or house that is occupied by any another sign or house lord), or if any of these five lords are placed in Dussthanas. Note, that to ascertain the placements of planets in houses one must refer to Bhava Chalit chart (Cuspal chart as per KP System). The planet that has no connection with Dussthanas (6th, 8th and 12th houses) is the shortlisted one that is subsequently worth a trial on another system.