Gemstones play a large role in Indian astrological practice. It is very common for Indians to wear a gemstone based on their lagnapati ("ascendant ruler" - the planet that rules the sign of their sidereal ascendant). For example, if your rising sign is Sagittarius, you would wear a yellow sapphire. People also often were gemstones for their current vimshottari dasha ruler.

It is a basic astrological principle that the condition of your ruling planet is crucial to your success in life. If your ascendant lord is afflicted or poorly placed in your chart, you can suffer a wide range of problems, from health difficulties to relationship tragedies to serious lack of career progress. You are, in a sense, the "child" of your ascendant lord, and it is its job to help you, protect you, and give you all that you need to thrive in life. But oftentimes it is two weak or damaged to fulfill its duties. This is where a gemstone can come in. By wearing the proper gemstone, it will contribute its energy to the energy of your ruling planet, blostering it and making it able to function properly to help you in life.

However, like any powerful tool, wearing a gemstone only works if it is the right stone. Just as much as wearing the right stone can help you, wearing the wrong stone can be detrimental to your wellbeing. It is crucial that your ascendant be calculated using the sidereal zodiac and a Indian-style birth chart.

Jyotish gemstones should be natural and of the highest quality affordable. They should be flawless, and cannot be died, heated, or chemically treated. To get noticeable effects, the gem should be larger than two carats and should be worn touching the skin. For example, if the stone is mounted in a ring, it should actually touch the skin of the finger. Because certain stones, such as diamonds that are free of all imperfections, are quite expensive at such large sizes, people often try to buy a smaller stone hoping to at least get some good effects. Another method is to wear several small stones whose carats add up to something over 2. Neither of these methods is effective, however. You must have a large, single, flawless stone to see any effects. If the primary gem is too expensive, it's better to get the secondary gem of the proper size and quality. Even a third or fourth choice of the right size and quality is preferable to more expensive stones of the wrong size or with flaws.

Here is a basic table of the planets, signs, and their recommended stones:

If you are interested in getting a prescription for an astrological gemstone, Mahesh can give you a precise recommendation.

Or, if you already know which stone is right for you, here is the place I highly recommend to get them. This company is run by people who know a lot about Vedic Astrology and gemstones, and can help you to get a stone that will be effective. Your neighborhood jeweler often does not understand the subtlelties involved in getting a stone that will actually work.