How to Choose a Lab-Grown Gemstone Retailer: 10 Things to Check Before You Buy

Lab-grown gemstones can offer exceptional color, clarity, and value, but not every seller provides the same level of disclosure, testing, or technical information.

Before buying a lab-grown ruby, sapphire, emerald, alexandrite, zircon, moissanite, diamond, or other laboratory-created gem, it is worth checking exactly what the seller is telling you about the material — and what they are not.

A good lab-grown gemstone retailer should clearly identify the gem, disclose how it was produced, explain any treatments, provide meaningful verification, and stand behind the authenticity of what it sells.

Here are 10 things to check before buying a lab-grown gemstone.

1. Is the gemstone clearly disclosed as lab-grown or synthetic?

The first requirement is simple: the seller should clearly state that the gemstone is laboratory-grown.

Terms such as:

• lab-grown
• laboratory-created
• laboratory-grown
• synthetic

describe a gemstone material that was produced artificially rather than mined from the Earth.

This does not mean that the material is fake.

A laboratory-grown ruby, for example, can be crystalline corundum with the same fundamental chemical composition and crystal structure as natural ruby. The difference is its origin.

What should concern buyers is vague terminology that obscures that origin.

A responsible retailer should make laboratory origin obvious in the product title or description rather than burying it in small print.

At Gemdrop®, laboratory origin is disclosed directly because we believe customers should know exactly what they are buying.

2. Does the seller identify the actual mineral <material> species?

Color alone does not identify a gemstone.

A red gem could be:

• ruby
• spinel
• garnet
• glass
• cubic zirconia
• another synthetic material

Likewise, an alexandrite-like color change does not automatically mean a gemstone is chrysoberyl alexandrite.

The seller should identify the underlying mineral or material, not simply use a trade name or color description.

For example:

Lab Ruby
Material: Corundum
Formula: Al₂O₃

Lab Emerald
Material: Beryl
Formula: Be₃Al₂Si₆O₁₈

This distinction is particularly important because materials with similar appearances can have very different refractive indices, densities, hardnesses, and optical behavior.

Gemdrop records the underlying gem material separately from appearance or trade terminology wherever appropriate.

3. Does the retailer disclose treatments?

Treatments can change the appearance of gemstones and may influence value, durability, and identification.

Depending on the material, treatments can include:

• heating
• irradiation
• diffusion
• coating
• filling
• impregnation
• other post-growth processes

Lab-grown gems can also undergo post-growth treatment.

A trustworthy seller should disclose known treatments rather than allowing customers to assume that a gemstone is untreated.

If treatment status is unknown, saying “unknown” is more scientifically responsible than making an unsupported claim.

4. Does the seller provide meaningful gemological data?

A good gemstone listing should contain more than color, size, and carat weight.

Useful gemological information can include:

• refractive index
• specific gravity
• hardness
• crystal system
• optic character
• birefringence
• fluorescence
• growth method
• transparency
• observed inclusions or features

Two especially useful properties are refractive index (RI) and specific gravity (SG).

Refractive index describes how strongly light bends when entering a material. Specific gravity describes density relative to water.

These values are useful because they help distinguish gemstone materials that can look very similar visually.

They should not, however, be treated as magical single-number identifiers. Many gemstones have ranges, and some readings depend on orientation, composition, equipment limitations, or structural variation.

Good gemology uses multiple observations together.

5. Has the gemstone actually been assessed or verified?

There is a major difference between a seller saying:

“This is a ruby.”

and being able to explain why they believe it is a ruby.

Useful verification methods can include combinations of:

• visual examination
• microscopy or loupe examination
• refractive index
• specific gravity
• polariscope observations
• ultraviolet fluorescence
• optical behavior
• growth features
• additional instrumental testing where appropriate

No single test is appropriate for every gemstone.

The strength of a gemological assessment comes from combining independent observations and checking whether they are consistent with the proposed identification.

At Gemdrop, gems are assessed using gemological observations and testing appropriate to the material, and verification information can be recorded against a unique Gemdrop® ID.

We also provide verification services for laboratories and sellers who want greater confidence in gemstone identity before offering material to customers.

6. Who is doing the testing?

Qualifications matter.

Gemstone testing involves mineralogy, crystallography, optics, chemistry, and materials science. A retailer making technical claims should ideally be able to explain who is responsible for those claims and what relevant expertise they have.

At Gemdrop, scientific oversight is provided by a PhD-qualified geologist.

That does not mean every gemstone requires an academic research project. It means that when questions arise about mineral identity, crystal growth, optical properties, or unusual observations, customers can speak with someone who understands the science behind the material.

We also believe customers should be able to ask questions rather than receiving only automated sales copy.

7. Is the growth method disclosed?

Not all lab-grown gemstones are produced in the same way.

Common crystal-growth methods include:

• Flame Fusion / Verneuil
• Czochralski pulling
• Hydrothermal growth
• Flux growth
• HPHT diamond growth
• CVD diamond growth

The growth method can influence cost, crystal quality, inclusions, zoning, available sizes, and characteristic internal features.

For example, laboratory-grown corundum may be produced by flame fusion or Czochralski growth, while laboratory-grown emerald is commonly produced hydrothermally or by flux growth.

A retailer does not necessarily need to identify the growth method for every inexpensive gemstone, but where that information is known, disclosing it provides useful additional transparency.

At Gemdrop, growth method is always recorded.

8. Can you trace the gem back to a record?

Traceability is increasingly important in gemstone retail.

At a basic level, traceability means being able to connect the gemstone you receive with the information supplied when you bought it.

Useful identifiers can include:

• unique gem ID
• batch or inventory number
• weight
• dimensions
• photographs
• testing record
• growth method
• date assessed
• verification page

Gemdrop uses unique Gemdrop® IDs and verification records so that gemstone information can remain associated with the individual gem or product.

For customers, this creates a permanent point of reference rather than relying solely on a product page that may eventually disappear after an item sells.

9. Is the pricing transparent and believable?

Laboratory-grown gemstone pricing varies enormously.

Price depends on factors including:

• gemstone material
• crystal-growth method
• size
• cut
• color
• clarity
• cutting quality
• unusual shapes
• manufacturing yield
• supply
• testing and documentation
• retail overhead

A higher price does not automatically mean a better gemstone.

Likewise, an extremely low price should not automatically be interpreted as fraud. Some synthetic materials can genuinely be produced economically.

The important question is whether the seller clearly describes what you are paying for.

A well-cut flame-fusion sapphire and a Czochralski-grown sapphire may both be laboratory-grown corundum, yet their production costs can differ substantially.

Comparing price makes sense only after comparing the actual material and specifications.

10. Does the retailer stand behind the gemstone?

Finally, look at what happens after you buy.

Check:

• return policy
• authenticity guarantee
• customer support
• documentation
• ability to answer technical questions
• what happens if the gemstone is found to be incorrectly identified

A seller confident in its identification should be prepared to stand behind it.

Gemdrop provides a Lifetime Authenticity Guarantee on its gems and maintains verification records designed to give customers continued confidence in what they purchased.

Customers can also contact us with questions about gem identity, testing, growth methods, or recorded verification information.

Quick checklist: what should a good lab-grown gemstone retailer tell you?

Before buying, you should ideally be able to answer:

Lab-grown gemstone verification at Gemdrop®

Gemdrop® was built around a simple principle:

Customers should know what they are buying.

Our laboratory-grown gems are assessed and recorded using appropriate gemological observations and testing, with scientific oversight from a PhD-qualified geologist.

Where applicable, records can include information such as:

• gem species
• laboratory-grown origin
• growth method
• dimensions
• weight
• color
• clarity
• refractive index
• specific gravity
• optical observations
• fluorescence
• assessment methods
• unique Gemdrop® identification

Gemdrop also works with laboratories, suppliers, designers, and sellers who need gemstone assessment or verification before material is offered to customers.

We believe transparency strengthens the laboratory-grown gemstone industry.

The goal is not simply to sell beautiful gems.

It is to make it easier for customers to understand exactly what those gems are.

FAQ

Are lab-grown gemstones real gemstones?

A laboratory-grown gemstone can have essentially the same mineral composition and crystal structure as its natural counterpart. The principal difference is that it was produced in a laboratory rather than forming naturally within the Earth.

The exact terminology depends on the material, so the underlying mineral identity should always be stated.

Is lab-grown the same as imitation?

No.

A synthetic or lab-grown ruby is corundum produced artificially.

A ruby imitation may simply be another red material made to resemble ruby.

Those are fundamentally different concepts.

How can you tell what a lab-grown gemstone is?

Gemologists use multiple physical and optical properties, potentially including refractive index, specific gravity, microscopy, polarization behavior, fluorescence, spectroscopy, and characteristic growth features.

No single test is universally sufficient.

Is cubic zirconia the same as zircon?

No.

Zircon is zirconium silicate, ZrSiO₄.

Cubic zirconia is zirconium dioxide, ZrO₂.

They are entirely different materials despite the similarity in their names.

Should a lab-grown gemstone come with documentation?

For inexpensive gems, formal laboratory reports are not always economically practical.

However, sellers should still clearly identify the material and laboratory-grown origin and should be able to provide meaningful supporting information.

For higher-value or unusual material, independent or retailer-based assessment records can provide additional confidence.