Gemstones have been valued for centuries for their colour, beauty, rarity, durability and use in jewellery, collecting and traditional astrological practices.
But buying a gemstone can be confusing. Terms such as natural, certified, treated, heated, lab-grown, synthetic, carat, ratti and origin are often used together, even though they describe different characteristics.
This LisaSimmi Gemstone Guide explains the basics so you can understand what you are buying before choosing a stone.
Astrological gemstone associations mentioned in this guide are based on traditional beliefs and are not scientifically proven guarantees of health, wealth, relationships, career or other outcomes.
What Is a Gemstone?
A gemstone is a natural, synthetic or sometimes organic material valued for qualities such as beauty, colour, rarity and durability and prepared for jewellery, ornamentation or collecting.
Many gemstones are minerals, but not every gemstone is technically a mineral. Pearl, for example, is an organic gemstone material.
Gemstones vs Crystals: What Is the Difference?
The words gemstone and crystal are often used interchangeably in everyday shopping, but they are not identical.
A crystal usually refers to a material with an organised crystalline structure, while a gemstone is a material selected and prepared for ornamental or jewellery use because of properties such as colour, beauty and durability.
If you are looking for information about Amethyst, Rose Quartz, Citrine, Pyrite and everyday crystal forms, visit our Crystal Guide.
Read the LisaSimmi Crystal Guide
Natural, Synthetic and Imitation Gemstones
Natural Gemstones
Natural gemstones are formed through natural geological or biological processes rather than being manufactured entirely in a laboratory.
However, natural does not automatically mean untreated. A natural gemstone may still have undergone treatments intended to improve its colour, clarity or appearance.
Synthetic or Lab-Grown Gemstones
Synthetic gemstones are manufactured in controlled environments but can have essentially the same chemical composition and crystal structure as their natural counterparts.
They should be clearly disclosed as synthetic or lab-grown rather than represented as naturally mined stones.
Imitation Stones
An imitation may simply resemble another gemstone visually without sharing the same chemical composition or physical properties.
Glass and cubic zirconia, for example, can be used to imitate the appearance of other gemstones.
How to Choose a Gemstone
Before buying a gemstone, consider why you want it.
- Jewellery: Focus on appearance, durability, size and setting.
- Collecting: Consider rarity, quality, origin, treatment and documentation.
- Gifting: Colour, symbolism, birthstone associations and personal preference may matter.
- Traditional astrology: Gemstone selection is traditionally linked with an individual birth chart rather than simply choosing the most popular stone.
Whatever your reason, always check the actual product information rather than relying only on the gemstone name.
Important Gemstone Quality Factors
1. Colour
Colour is one of the most noticeable characteristics of a gemstone. Hue, tone, saturation and colour distribution can all affect appearance and value.
A deeper colour is not automatically better in every gemstone. The desirable colour range depends on the particular stone.
2. Clarity
Natural gemstones may contain inclusions, internal features, growth patterns or surface characteristics.
Some inclusions are expected in particular gemstone varieties. A completely flawless appearance should not automatically be assumed to mean better or more natural.
3. Cut
Cutting determines the gemstone's shape, proportions and how effectively it reflects light.
A well-executed cut can significantly improve the appearance of a gemstone.
4. Carat Weight
Carat is a standard unit of gemstone weight.
1 carat = 0.2 grams.
Two stones with the same carat weight may still have very different prices because gemstone value also depends on colour, clarity, treatment, origin, rarity and overall quality.
5. Treatment
Gemstones can undergo treatments intended to improve colour, clarity or durability.
Common gemstone treatments may include:
- Heating
- Oil or resin filling
- Dyeing
- Coating
- Irradiation
- Diffusion
- Fracture filling
Treatments are not automatically a sign that a gemstone is fake. What matters is that relevant treatments are accurately disclosed.
What Does a Gemstone Certificate Tell You?
A gemstone certificate or laboratory report is intended to provide identification information about the examined stone.
Depending on the laboratory and gemstone, a report may include:
- Gemstone identity
- Natural or synthetic status
- Weight
- Measurements
- Shape and cut
- Colour
- Treatment observations
- Origin opinion, where applicable and where the laboratory provides it
A certificate does not automatically mean that a gemstone is untreated, premium quality or suitable for a particular astrological purpose.
Always read the actual report details rather than relying only on the word “certified.”
Popular Gemstones and Their Indian Names
Yellow Sapphire – Pukhraj
Yellow Sapphire is the yellow variety of corundum and is commonly known as Pukhraj in India.
In traditional Vedic astrology, Yellow Sapphire is associated with Jupiter. It is commonly selected for jewellery as well as traditional astrological use.
When comparing Yellow Sapphires, check colour, clarity, carat weight, treatment information and certification details where provided.
Shop Yellow Sapphire (Pukhraj)
Blue Sapphire – Neelam
Blue Sapphire is a blue variety of corundum and is popularly known as Neelam.
In traditional Vedic astrology, Blue Sapphire is associated with Saturn.
Blue Sapphire can vary widely in colour, clarity, treatment and value, so the individual stone details should always be reviewed carefully.
Ruby – Manik
Ruby is the red variety of corundum and is commonly called Manik or Manikya in India.
In traditional Vedic astrology, Ruby is associated with the Sun.
Ruby colour can range from lighter red tones to deeper reds. Treatments are also common in the ruby market, so disclosure and laboratory information can be important when purchasing.
Emerald – Panna
Emerald is a green variety of the mineral beryl and is commonly known as Panna.
In traditional Vedic astrology, Emerald is associated with Mercury.
Natural Emerald commonly contains inclusions, and clarity enhancement using oil or similar materials is widely encountered in the gemstone trade.
Pearl – Moti
Pearl, commonly called Moti in India, is an organic gemstone material rather than a mineral crystal.
In traditional Vedic astrology, Pearl is associated with the Moon.
Pearls can differ according to type, size, shape, colour, surface quality, lustre and whether they are natural or cultured.
Opal
Opal is known for the optical phenomenon called play-of-colour in many varieties.
Individual Opals can differ dramatically in body colour, pattern, transparency and colour play.
Hessonite – Gomed
Hessonite is a variety of garnet commonly known as Gomed in India.
In traditional Vedic astrology, Hessonite is associated with Rahu.
Colour commonly ranges through honey, brownish-orange and reddish-brown tones.
Explore Other Natural Gemstones
Gemstones extend far beyond the traditional astrological stones. LisaSimmi may also offer stones such as Amethyst, Citrine, Garnet, Peridot, Blue Topaz, Green Aventurine and other varieties depending on current stock.
What Are Navratna Gemstones?
Navratna means “nine gems” and refers to a traditional group of nine gemstone materials associated with the nine planetary influences of Indian astrology.
The traditional Navratna group includes:
- Ruby – Sun
- Pearl – Moon
- Red Coral – Mars
- Emerald – Mercury
- Yellow Sapphire – Jupiter
- Diamond – Venus
- Blue Sapphire – Saturn
- Hessonite – Rahu
- Cat's Eye – Ketu
These planetary associations belong to traditional astrological systems and should not be interpreted as scientifically demonstrated effects.
Should You Choose a Gemstone Only by Zodiac Sign?
Not necessarily.
Birthstone jewellery and zodiac jewellery can be chosen according to personal preference, birthday or star sign.
Traditional Vedic astrological gemstone recommendations, however, are more individualised and may consider factors such as planetary placements, ascendant, house rulership and the overall birth chart.
This is why an expensive gemstone should not automatically be purchased for astrological use simply because it is commonly associated with a particular zodiac sign.
How to Read a Gemstone Product Page
Before purchasing, check whether the listing provides relevant information such as:
- Gemstone name
- Product photographs
- Weight or carat weight
- Dimensions
- Colour
- Shape and cut
- Treatment information where applicable
- Origin information if stated
- Certification details where applicable
- Return and exchange policy
Never assume information that is not stated on the individual product page.
Does Gemstone Origin Matter?
Certain geographic origins can be commercially desirable for some gemstones, but origin alone does not determine quality.
A beautiful gemstone from one location can be better than a lower-quality stone from a famous origin.
If origin is important to your purchase, rely on product-specific documentation or a recognised laboratory opinion rather than appearance alone.
How to Care for Gemstones
Different gemstones have different hardness, toughness, porosity and sensitivity to heat or chemicals.
As a general precaution:
- Avoid harsh household chemicals.
- Remove gemstone jewellery before heavy physical work.
- Keep pieces away from unnecessary impact.
- Store jewellery separately to reduce scratching.
- Use a soft cloth for routine cleaning.
- Do not assume every gemstone can be soaked in water.
- Avoid ultrasonic or steam cleaning unless you know the particular stone and treatment can safely tolerate it.
Always follow care recommendations for the specific gemstone and jewellery setting.
Natural Inclusions and Variation
Natural gemstones can contain inclusions, colour zoning, internal growth features and surface characteristics.
These features mean that two natural stones of the same variety may not look identical.
Product photographs, measurements and stone-specific information should therefore be checked carefully when purchasing an individual gemstone.
Frequently Asked Questions About Gemstones
Does certified mean untreated?
No. A certified gemstone may still be treated. The laboratory report should be read to understand what identification and treatment information has actually been provided.
Is a natural gemstone always more expensive?
Not necessarily. Price depends on many factors including variety, colour, clarity, cut, size, treatment, rarity, origin and market demand.
Are gemstone inclusions bad?
Not automatically. Natural gemstones commonly contain inclusions. Their effect on beauty, durability and value depends on the stone and the nature of the inclusion.
Are heated gemstones fake?
No. A naturally formed gemstone can remain natural even after heat treatment. Treatment should, however, be properly disclosed where relevant.
What is the difference between carat and ratti?
Carat is the internationally standardised unit of gemstone weight. Ratti is a traditional Indian unit whose exact conversion can vary depending on the convention being used. When buying, rely on the actual carat or gram weight stated by the seller or laboratory rather than assuming a universal ratti conversion.
Which gemstone should I wear for astrology?
Traditional astrological recommendations are individual-specific. A gemstone should not be chosen solely because it is expensive, popular or associated with a particular Sun sign.
Explore LisaSimmi Gemstones
Browse the LisaSimmi gemstone collection by stone type and review each individual product page for available information about size, weight, treatment and certification.
Shop All Gemstones | Yellow Sapphire | Blue Sapphire | Ruby | Other Gemstones
Disclaimer: Astrological and spiritual gemstone associations described on LisaSimmi are based on traditional beliefs and practices. They do not guarantee health, financial, career, relationship or other outcomes. Product-specific gemstone identity, treatment and certification information should always be checked on the individual listing where applicable.