Diamond Imitations: What Is Moissanite and How Can You Tell It Apart from a Diamond?

At Urbieta Antique, an antique and vintage jewellery specialist based in Madrid, Spain, we work with natural diamonds, including antique and reclaimed old-cut diamonds selected from historic jewellery. Although moissanite can look remarkably similar to a diamond at first glance, the two gemstones differ significantly in composition, optical properties, origin, rarity and value. Understanding these differences is essential when buying antique diamond jewellery and helps collectors and buyers identify exactly what type of gemstone they are purchasing.

At first glance, moissanite can easily be mistaken for a diamond. It is transparent, exceptionally brilliant and highly durable, characteristics that have made it one of the best-known alternatives to diamonds in contemporary jewellery.

However, moissanite and diamond are not the same.

Their composition, optical properties, origin, rarity and value are different and, although they may look similar visually, a specialist examination can distinguish between them.

At Urbieta Antique, an antique and vintage jewellery specialist based in Madrid, Spain, we work with natural diamonds, including antique and reclaimed old-cut diamonds selected from historic jewellery. Understanding the differences between diamonds and their possible imitations is therefore an essential part of our work.

After exploring the differences between diamonds and cubic zirconia on our blog, we continue our series on diamond imitations and alternatives with one of the gemstones that currently raises the most questions: moissanite.

What exactly is it? Why does it sparkle so much? Can it be mistaken for a diamond? And what should you consider when buying jewellery containing one of these stones?

What Is Moissanite?

Moissanite is silicon carbide, a material whose optical and physical properties allow it to be used as a gemstone.

Its history is particularly interesting. The mineral was identified in the late 19th century by French scientist Henri Moissan, who would later receive the Nobel Prize in Chemistry.

Natural moissanite is extremely rare. For this reason, virtually all moissanite used in jewellery today is lab-created moissanite.

This distinction is important because there can sometimes be confusion surrounding the term. The fact that moissanite occurs naturally does not mean that the stones commonly used in jewellery have been extracted from natural deposits.

Today, moissanite is produced under controlled conditions to create transparent, durable gemstones with exceptional brilliance.

Moissanite and Diamond: Two Different Gemstones

Although moissanite can be used as a visual alternative to diamond, from a gemmological perspective they are completely different materials.

A diamond consists of crystallised carbon, while moissanite is made from silicon carbide.

They also differ in hardness, light refraction, dispersion, density and other physical properties.

These characteristics allow a specialist to distinguish one gemstone from the other.

For Urbieta Antique, this distinction is fundamental. When we select an antique diamond jewel, we do not simply assess whether its stones are transparent and brilliant. We study their characteristics, and the pieces are subsequently certified so that clients know exactly what they are purchasing.

Appearance should never replace gemmological identification.

Moissanite vs Diamond: What Are the Main Differences?

One of the most common searches made before purchasing jewellery is “moissanite vs diamond”.

Although the two may appear similar, there are important differences.

1. Composition

This is the fundamental difference.

Diamond is crystallised carbon. Moissanite is silicon carbide.

Moissanite is therefore neither a type of diamond nor a lower-quality diamond. They are two entirely different materials.

2. Origin

Natural diamonds form deep within the Earth through geological processes involving enormous pressures and temperatures over extremely long periods of time.

Natural moissanite exists but is extraordinarily scarce. The moissanite stones sold for jewellery today are predominantly created in laboratories.

This difference is particularly important when discussing antique jewellery.

The diamonds found in a ring dating from the late 19th or early 20th century form part of the history of the piece itself. At Urbieta Antique, we also recover antique diamonds for selected pieces in our Urbieta Originals collection, allowing existing gemstones to begin a new chapter.

3. Brilliance and Fire

Moissanite is an exceptionally brilliant gemstone.

In fact, it has greater light dispersion than diamond, which means it can produce particularly intense flashes of colour, commonly referred to as fire.

This characteristic can be visually attractive, but it is also one of the ways in which the two gemstones can differ in appearance.

Diamond interacts with light differently, displaying its own characteristic balance between white brilliance and coloured dispersion.

The larger the stone, the easier it can become to notice these differences.

4. Hardness

Diamond reaches 10 on the Mohs hardness scale, making it the hardest naturally occurring material commonly used in gemmology.

Moissanite is also extremely hard, measuring approximately 9.25 on the Mohs scale, which makes it highly resistant and suitable for jewellery intended for frequent wear.

Moissanite is therefore significantly more resistant to scratching than other diamond simulants such as cubic zirconia.

5. Price and Value

This is probably one of the differences that most influences purchasing decisions.

Lab-created moissanite is considerably less expensive than a natural diamond of comparable visual appearance and dimensions.

However, comparing these gemstones purely in terms of price would oversimplify the issue.

In an antique diamond jewel, value is not determined solely by the gemstones. Age, design, setting, materials, craftsmanship, condition, rarity and historical coherence of the piece also play an important role.

At Urbieta Antique, we value precisely this combination of qualities.

Is Moissanite a Synthetic Diamond?

No.

This is an especially important distinction.

A moissanite is not a synthetic diamond or a lab-grown diamond.

A laboratory-grown diamond has essentially the same chemical composition and crystalline structure as a natural diamond, although it has been produced artificially.

Moissanite, by contrast, has a different chemical composition.

It is therefore important to distinguish between three concepts that are often confused: natural diamonds, lab-grown diamonds and moissanite.

They may share certain visual characteristics, but gemmologically they are different materials.

Is Moissanite a Diamond Imitation?

There is an important nuance here.

Moissanite is a gemstone in its own right and possesses its own distinctive properties. However, when it is cut and marketed to resemble a diamond, it acts as a diamond simulant or visual alternative to diamond.

This also distinguishes it from synthetic diamonds.

A synthetic or laboratory-grown diamond attempts to reproduce the characteristics of a natural diamond through technology. Moissanite does not reproduce the chemical composition of diamond; it simply offers a potentially similar visual appearance.

That is why knowing exactly what gemstone a piece of jewellery contains is essential.

How Can You Tell Moissanite from a Diamond?

Distinguishing between the two with the naked eye can be difficult, particularly for someone without gemmological knowledge.

One of the best-known differences relates to the way each gemstone interacts with light. Moissanite’s high dispersion can produce more intense flashes of colour than those typically seen in diamonds.

Moissanite also exhibits double refraction, an optical property that can cause certain facets to appear doubled when examined under magnification from particular angles.

Professionals also use specialised instruments to analyse the properties of gemstones.

At Urbieta Antique, we strongly recommend avoiding excessive reliance on so-called home tests for identifying diamonds.

Fogging a stone, attempting to scratch glass or carrying out other domestic tests does not provide a reliable identification and, in some cases, could even damage the jewellery.

When there is genuine doubt, professional gemmological analysis is the appropriate solution.

Can Moissanite Pass a Diamond Tester?

This is another frequently asked question.

Some older diamond testers rely primarily on thermal conductivity. Because of moissanite’s physical properties, certain devices may produce readings that can cause confusion.

Modern professional testing equipment incorporates additional methods that make it easier to distinguish between the two materials.

For this reason, gemstone identification should not depend solely on a single test.

At Urbieta Antique, our pieces are inspected and certified, ensuring that gemstone identification does not rely on visual impressions or domestic testing methods.

Moissanite vs Cubic Zirconia: Are They the Same?

No.

Cubic zirconia is synthesised zirconium dioxide and is another of the most widely recognised diamond simulants.

Moissanite is harder and has different optical properties. It also generally carries a higher price than cubic zirconia.

Both materials can be used as visual alternatives to diamonds, but they are completely different from one another.

This distinction complements our previous Urbieta Antique content about diamonds and cubic zirconia and helps explain why not all transparent gemstones used as diamond substitutes are the same.

Which Is Better: Moissanite or Diamond?

There is no universal answer because it depends on what the buyer is looking for.

Moissanite may appeal to someone who prioritises a larger stone, intense brilliance, excellent durability and a lower price.

Natural diamonds represent something different: natural rarity, distinctive gemmological characteristics and a long-standing tradition within the history of jewellery.

When discussing antique diamonds, there is another element that is particularly important to Urbieta Antique: historical value.

An antique diamond cut was not designed to imitate a stone created today. Its proportions, facets and subtle irregularities reflect the techniques used by the craftspeople who cut it and the historical period to which it belongs.

This is why our focus is on natural diamonds and, particularly, antique and reclaimed diamonds.

Antique Diamonds: The Choice of Urbieta Antique

At Urbieta Antique, we search for antique and vintage jewellery in different parts of the world, bring these pieces to Madrid and carry out a careful restoration process before finding them a second life.

Many of these pieces contain natural old-cut diamonds that are inseparable from their history.

We have also extended this philosophy to Urbieta Originals, our contemporary collection inspired by antique and vintage jewellery designs.

These pieces incorporate reclaimed old-cut diamonds, combining contemporary craftsmanship with gemstones that already have a previous history.

For us, this is a significant part of their appeal.

We are not simply looking for a gemstone that shines like a diamond.

We look for diamonds with a story to tell.

Why Certification Matters When Buying Diamond Jewellery

When purchasing jewellery of significant value, knowing exactly which gemstones it contains is essential.

Moissanite can be a perfectly valid choice, provided that the buyer knows they are purchasing moissanite and that the price reflects this.

Problems arise when a gemstone is presented as something it is not.

That is why all Urbieta Antique pieces are certified and supplied with the corresponding certificate issued by an independent gemmological laboratory.

This certification provides objective information about the jewellery and its gemstones and is especially valuable when dealing with antique and vintage jewellery.

Trust in a piece of jewellery begins with knowing exactly what you are buying.

Buying Natural Diamond Jewellery from Urbieta Antique

Our collection includes rings, solitaire rings, cluster rings, three-stone rings, five-stone rings, earrings, pendants and other antique and vintage jewellery featuring natural diamonds, as well as our Urbieta Originals collection.

Each antique piece is individually selected according to its diamonds, design, historical period, setting, craftsmanship and condition.

Because we specialise in unique pieces, our collection changes continuously. Once a piece finds a new owner, it may not always be possible to replace it with an identical example.

If you are looking for diamond jewellery, our team can help you understand the characteristics of each piece and what makes it distinctive.

Because moissanite and diamond may look similar at first glance, but they are not the same.

And for Urbieta Antique, understanding that difference is part of something essential: knowing exactly what history we are holding in our hands.

Frequently Asked Questions About Moissanite and Diamonds