What this tool does
Gemstones are a recognised remedy in Vedic astrology, and a common first question is which stones belong to which rising sign. This tool answers it from your birth details. It finds your ascendant, then reads off the table that the tradition teaches for that sign, and sets it beside where each of those planets actually stands in your chart. It sells nothing, and it recommends nothing: it shows the scheme and the facts so that you can discuss them with an astrologer you trust.
The scheme is exactly the one on the twelve gemstone pages of the site, for example Taurus ascendant, so the two always agree.
How the result is worked out
From the date, time and place of birth the tool works out the rising sign (sidereal, Lahiri ayanamsa) and the planets. Counting whole signs from the rising sign, it finds the lords of the 1st, 5th and 9th houses. The scheme then reads as follows. The stone of the lagna lord is the life stone. The stones of the 5th and 9th lords, the trine lords, are the other stones usually considered. A yogakaraka, a planet that rules both an angle (the 4th, 7th or 10th house) and a trine (the 5th or 9th), is added, because the tradition gives such a planet special standing for that rising sign.
The stones usually avoided are those of planets that rule only the 6th, 8th or 12th house. A planet that rules one of those houses and also the 1st, 5th or 9th is called mixed, and is weighed case by case. The planet-to-stone pairs are the usual ones: ruby for the Sun, pearl for the Moon, red coral for Mars, emerald for Mercury, yellow sapphire for Jupiter, diamond for Venus and blue sapphire for Saturn, with hessonite and cat’s eye for Rahu and Ketu, which rule no sign and are judged from their placement.
Why your chart is shown beside the scheme
A table built only from the rising sign cannot tell you whether a planet is strong or struggling in your own chart, and tradition says that is what decides the advice. So for each stone on the list the tool shows the planet’s sign, house and condition. A planet that is exalted or in its own sign is described as already strong, and the classical reasoning sees the least for a stone to add. A planet that is debilitated, combust or in the 6th, 8th or 12th house is in the condition where readers most often discuss support, and only after a full reading and usually after conduct and mantra. An ordinary placement means the question rests on the dasha and on the chart as a whole.
None of this is a prescription. The dasha now running, the aspects, the navamsa and the whole chart all enter a real reading, and the tool shows only the first step.
How to use the result
Treat the result as a list of questions. Read the page for your rising sign, then the page for any stone that interests you, from the gemstones hub. The pages cover the finger, metal and day, the stones’ substitutes, and the care to take over treated and synthetic stones. If you go on to buy, how to buy a gemstone lists the red flags. Most traditional advice puts the older, cheaper steps first: conduct, giving, and mantra for the planet, and the Navagraha mantras page gathers them.
Check the rising degree too. If it is within a degree of a sign boundary, the tool warns you, because the ascendant moves about one degree every four minutes and a small error in the birth time could change the whole list. The Ascendant calculator shows the same degree with its nakshatra.
Frequently asked questions
↳ Which stone does the tool call my life stone?
The stone of the lagna lord, the ruler of your rising sign. Tradition treats it as the main stone for that ascendant, subject to the planet's condition in your chart.
↳ Does the tool tell me to buy a stone?
No. It shows the traditional scheme for your rising sign and the condition of each planet, for education. A stone is an optional remedy, and a full chart reading comes before any decision.
↳ Why are some stones marked usually avoided?
Because the planet rules only the 6th, 8th or 12th house, and astrologers usually prefer not to strengthen such a planet. It is a tendency, and a reader may weigh a planet differently in a particular chart.
↳ What if my birth time is not exact?
The rising sign depends on it, and so does the whole list. If your rising degree is near the end of a sign the tool warns you, and then it is worth checking the birth time before reading further.
↳ Where are Rahu and Ketu in this scheme?
They rule no sign, so their stones, hessonite and cat's eye, are not part of the ascendant list. They are judged from where the nodes stand, and the tool shows that placement.