Which Gemstone Should You Wear, By Your Date of Birth

This gives the stone tied to the graha ruling your Mulank, along with the weekday, finger and metal traditionally used with it. You need only your date of birth.

The manual method

  1. Reduce your day of birth to a single digit to find your Mulank.
  2. Identify its ruling graha.
  3. Take that graha's stone — Ruby for Sun, Pearl for Moon, Yellow Sapphire for Jupiter, Hessonite for Rahu, Emerald for Mercury, Diamond or white sapphire for Venus, Cat's Eye for Ketu, Blue Sapphire for Saturn, Red Coral for Mars.
  4. Wear it on the graha's weekday, in the traditional metal and finger for that stone.

Carat to ratti — both standards, so you can check a quote

What this page can and cannot tell you

It can tell you which stone the classical tables attach to the graha ruling your Mulank. That mapping is fixed, published, and the same one used everywhere else on this site — it is read from a single table rather than restated per page, so it cannot quietly differ from what the compatibility pages say.

It cannot tell you that a stone will change your luck, your health or your income. A ruling graha is derived from one digit of a birth date, and one digit cannot carry a claim that size. Sites that promise it are selling something; we would rather you check the arithmetic and decide for yourself.

It also cannot read a birth chart. A full ratna recommendation in Vedic practice weighs planetary strength, dasha period and current transits, which need a birth time and place we do not ask for and do not compute. If someone is about to spend a significant sum, that consultation is a real thing and this page is not a substitute for it.

Two ways to arrive at a stone, and they disagree

There are two defensible derivations and this page runs both. The first takes your Mulank — the day of the month you were born, reduced to a digit — finds its ruling graha, and takes that graha's ratna. It needs only a date.

The second is the more orthodox one in Vedic practice: your Moon sign gives a rashi, the rashi has a lord, and the lord has its stone. It needs a birth time, because the Moon changes rashi roughly every two and a quarter days. On about 43% of days a date alone does not settle which sign the Moon was in, and where that happens we show every candidate rather than choosing.

The two routes disagree more often than they agree. Someone born on 12 April 1992 at noon IST has Mulank 3, which points to Yellow Sapphire, and a Karka Moon, which points to Pearl. Neither is a mistake — they are different questions. We publish both and name the disagreement, because averaging two traditions gives you a stone that neither of them actually recommends, and at these prices that is not a small thing.

This is also the honest answer to why two websites give you different stones. Usually neither says which method it used.

The two rattis — why the same weight means two things

A metric carat is exactly 200 milligrams and never varies. The ratti does. It began as the weight of a single Abrus precatorius seed and was never standardised, and two values are in common use: the pakki ratti at about 182.25 mg, which is what astrological gemstone dealers normally mean, and the kacchi or goldsmith's ratti at about 121.5 mg.

That gap is not academic. A stone quoted as 5 ratti is 4.56 carats under the pakki standard and 3.04 carats under the kacchi — the same spoken number describing stones that differ by a third in weight, and therefore by far more in price once you are into five figures.

So when a price is quoted in ratti, ask which ratti, and ask for the weight in carats or milligrams as well. A dealer who will not put a metric weight in writing is telling you something. The conversion table on this page is computed from those two constants, so you can check any quote against it yourself.

How weight is usually decided

The convention most often quoted is roughly one ratti for every ten kilograms of body weight, and separately each stone carries a minimum below which practitioners consider it ineffective. The two rules disagree frequently, and practitioners disagree about which should win.

We are not going to name a figure for you. The limits note above is the position this site takes and it has not changed: carat weight should be set by someone who can see you. What we will do is show both numbers, so that when a figure is quoted to you, you can tell whether it follows either convention or neither.

What this number does not tell you

Carat weight depends on body weight and should be set by someone who can see you; no honest calculator can name a figure. A gemstone is never a substitute for medical treatment or for a decision that needs making.

Frequently Asked Questions

How many carats is 5 ratti?

It depends which ratti. Under the pakki standard used for astrological stones (182.25 mg) it is about 4.56 carats. Under the goldsmith's kacchi ratti (121.5 mg) it is about 3.04 carats. A metric carat is fixed at 200 mg, so always ask for the weight in carats as well as ratti before agreeing a price.

Can I wear a gemstone without consulting anyone?

For the lighter stones, generally yes. Blue Sapphire is the traditional exception — it is said to act quickly in either direction, and the convention is to test it before wearing it permanently.

Does the stone have to be expensive?

No. The tradition asks for a natural, untreated stone in contact with the skin, not a large one. A small clean stone is preferred over a large treated one, and cost is not the measure.

Every table on this page is published in full, with what we will and will not compute, on our how we calculate page.

Related free calculators

One number, or all of them

A calculator answers one question at a time. The complete numerology report works out your Mulank, Bhagyank and name number in one place and shows where they agree and where they pull against each other, with every calculation printed.