A gemstone bought for astrology is bought twice over: once as a piece of jewellery with a market value, and once as a remedy with a meaning for you. The second part cannot be checked by anyone, but the first can, and it is where most disappointment arises. This page explains the differences between natural, treated and synthetic stones, what laboratory reports say, how carats and ratti work, how to think about prices, and what red flags to look for. It is written to protect you. We sell nothing but the reading, so we have no stone to push.
First, the chart
Before price and quality, the question is whether you need a stone at all. The usual order in the tradition is conduct, then mantra and giving, then temple visits, and only then a gem. The planet’s condition in your own chart decides whether support is wanted, and the stone to consider depends on the planet’s role for your ascendant. The gemstones hub explains this, and the stone pages (ruby, pearl, red coral, emerald, yellow sapphire, diamond, blue sapphire, hessonite and cat’s eye) go stone by stone. Nobody honest will rush you.
Natural, treated and synthetic: the vocabulary
Three words cover most of what you will be offered.
- Natural: formed in the earth without human help. A natural stone may still be treated.
- Treated or enhanced: a natural stone changed to improve colour or clarity. Common treatments are heating (ruby and sapphire), oiling or resin filling (emerald), dyeing (coral, pearl) and bleaching. Heating is accepted in the trade when disclosed. Glass filling and heavy resin lower the value a great deal.
- Synthetic or lab-grown: made in a laboratory with the same chemistry as the natural stone. It is a real ruby or sapphire in composition, but not a natural one. It is a legitimate product when sold as such, at a far lower price.
- Imitation or simulant: a different material made to look like the stone, such as glass or coloured quartz. It is not the stone at all.
Whether the tradition prefers natural, untreated stones is a question on which astrologers differ. Many do, some accept disclosed heating, and few have a clear view on lab-grown stones. Whatever you decide, the thing to insist on is honest naming.
Laboratory certificates
A laboratory report is the only dependable way to name a stone, because many treatments and synthetics cannot be seen by eye or a loupe. A good report states the species and variety, whether it is natural or synthetic, the treatments found, the weight and dimensions, and sometimes the origin. Reputable gem laboratories include international names such as GIA, SSEF, Gübelin and GRS, and Indian laboratories such as the Gemological Institute of India, IGI India and the Gem Testing Laboratory in Jaipur. Our list is only a few examples, and we cannot vouch for every laboratory.
Three cautions apply. First, check that the report number matches the stone you hold, and, where the laboratory offers an online report check, use it. Second, a report issued by the shop itself, or by a body you cannot find online, is only a description. Third, a report names what the stone is. It does not say whether the stone is suitable for you.
Carats, grams and ratti
A carat is a unit of weight for gems, equal to 0.2 grams. One carat is divided into 100 points. Ratti is the traditional Indian unit, based on the seed of a plant. Its modern value is commonly taken as roughly 0.9 carat, but sellers in different regions use different conversions, and some treat one ratti as one carat. That is why it is wise to ask for the weight in carats or grams, written on the invoice, and to ask how the seller converts.
Astrologers also differ on how heavy a stone should be. Some give a weight in ratti based on the stone and the person, others give no rule, and a larger stone is not stronger by that fact. Quality of colour, clarity and cut usually matter more than size, and a smaller, cleaner, honest stone is generally a better buy than a large, heavily flawed one.
Realistic prices, without live figures
We do not quote prices, because they move and vary widely by quality, origin and treatment. What can be said is how to think about them.
- Prices are per carat, and they usually rise faster than weight, so a stone twice the size may cost much more than twice as much.
- A natural, untreated stone of fine colour can cost many times a treated stone of the same size. Heated and glass-filled stones sit at the bottom of the scale.
- Different stones sit on different scales. A natural ruby, blue sapphire, emerald or diamond of quality is costly. Hessonite, carnelian, amethyst or citrine are modest. Pearl varies from inexpensive cultured strands to very costly natural pieces.
- Compare quotes from several sellers for stones with similar reports, and treat both a very high and a very low price as questions.
If a price seems too good to be true, the usual explanation is treatment, a different stone or a synthetic one.
Red flags
These do not prove dishonesty alone, but several together are a reason to walk away.
- Urgency: “buy today, the muhurat is now” or a countdown to a price rise.
- Guarantees: promises of marriage, wealth or cures. No stone can promise a result, and the tradition does not.
- No paper: no invoice, or an invoice that says only “gem” with no species, weight or treatment.
- Vague names: “Ceylon”, “Burma” or “Kashmir” with no report. Origin claims are among the hardest to prove.
- An astrologer who sells you the stone: it is possible for this to be honest, but it is a conflict of interest, so ask for a report and compare prices elsewhere.
- Fear: being told that something bad will happen unless you buy. Fear is a pressure tactic and not a part of the tradition.
- No returns: a good seller allows a reasonable period to have the stone tested independently.
A sensible way to buy
Start with a reading. Ask for the stone’s name, weight in carats and any treatment in writing. For stones of value, ask for a report from a recognised laboratory, and verify its number. Choose an open setting if the tradition you follow asks for the stone to touch the skin, and have it set only after you are satisfied. If the stone is for a trial, ask whether it can be returned. Keep the invoice and report together.
Where to go next
If you do not yet know your ascendant, the free birth chart tool will find it, and the house lords guide shows where your lords sit. If a main stone is out of reach, see the upratna substitute stones page.
Frequently asked questions
↳ Is a treated gemstone acceptable for astrology?
Opinions differ. Many astrologers accept disclosed heating, and some prefer untreated stones. Either way, the treatment should be stated in writing and reflected in the price.
↳ How many carats or ratti should I buy?
There is no single rule, and astrologers differ. Ask the reader who knows your chart, and always have the weight written in carats or grams, since ratti conversions vary.
↳ Do I need a laboratory certificate?
For any stone of real value, yes, because many treatments and synthetics cannot be seen by eye. Check that the report number matches the stone, and use the laboratory's own verification if it has one.
↳ Where should I buy an astrology gemstone?
Choose a seller who gives a written invoice, allows independent testing and does not rely on urgency or fear. Compare more than one quote before you decide.
↳ Do you sell gemstones?
No. We sell nothing but the reading, so nothing on this page is there to steer you toward a purchase from us.