What is Moissanite? A Complete Guide for Australian Jewellery Buyers
Moissanite is one of the most brilliant gemstones on earth. It is also one of the least understood. This guide covers what moissanite is, where it comes from, how it behaves, and what to look for when choosing a moissanite piece.
The Origins of Moissanite
Moissanite was first identified in 1893 by French chemist Henri Moissan while examining rock samples from a meteorite crater in Canyon Diablo, Arizona. Moissan initially believed he had found diamonds. On closer analysis, the crystals were identified as silicon carbide, a compound not previously found occurring naturally on Earth.
Natural moissanite is extraordinarily rare. The deposits Moissan found came from outer space, carried to Earth inside a meteorite. The silicon carbide that forms moissanite requires conditions that do not commonly occur in the Earth's crust.
Because natural moissanite is too rare for commercial use, the moissanite used in jewellery today is created in laboratory conditions. The process was developed in the 1990s and produces a gemstone that is chemically identical to the naturally occurring stone.
What Moissanite Is Made Of
Moissanite is composed of silicon carbide, a compound of silicon and carbon. Under specific conditions of heat and pressure, silicon carbide forms a crystal structure with optical and physical properties that make it well suited to jewellery use.
The crystal structure of moissanite gives it two distinctive optical qualities: a high refractive index and strong dispersion. These two properties together determine how the stone handles light.
Refractive Index
The refractive index measures how significantly light bends as it passes through a material. Moissanite has a refractive index of 2.65 to 2.69. Diamond's refractive index is 2.42. A higher refractive index means more light is bent as it passes through the stone, producing a more intense return of white light through the crown.
Dispersion
Dispersion is the separation of white light into spectral colours as it passes through a gemstone. This produces what is commonly called fire — the flashes of colour visible in a stone when it moves under light. Moissanite has a dispersion rate of 0.104, compared to 0.044 for diamond. This is why moissanite shows more coloured light flashes than diamond, particularly under direct or point-source lighting.
How Moissanite Is Grown
Laboratory-grown moissanite is produced through a thermal growing process. Silicon and carbon are combined under high temperatures in a controlled environment, where they form crystals over a period of several months.
Once grown, the raw crystals are cut and polished using the same techniques applied to other hard gemstones. The cut determines how light enters and exits the pavilion of the stone, which directly affects the appearance of the finished piece.
The process produces a gemstone that is physically, chemically, and optically identical to naturally occurring moissanite. There is no meaningful difference between laboratory-grown and naturally occurring moissanite beyond the circumstances of origin.
Moissanite Hardness and Durability
Hardness in gemstones is measured on the Mohs scale, which runs from 1 (softest) to 10 (hardest). Diamond is the hardest known natural material and sits at 10. Moissanite sits at 9.25.
For context:
Sapphire sits at 9. Moissanite sits at 9.25. Diamond sits at 10.
A rating of 9.25 makes moissanite resistant to scratching under everyday conditions. The materials capable of scratching moissanite are not commonly encountered in daily life. This durability makes it suited to pieces worn regularly, including rings, bracelets, earrings, and necklaces.
Moissanite is also thermally stable. It will not fracture under the heat conditions encountered in standard jewellery repair or resizing work.
Moissanite Colour Grading
Moissanite is graded on a colour scale similar to that used for diamonds, running from D (colourless) through to warmer tones further down the scale.
D, E, and F Colour
D, E, and F grade moissanite is colourless. Under most lighting conditions, including indoor and outdoor environments, these grades appear clear with no visible warmth or tint. D colour is the highest grade.
G, H, and I Colour
Near-colourless. Any warmth in these stones is generally only visible when the stone is examined in isolation against a white background, or compared directly alongside a D colour stone. In a finished piece of jewellery under normal conditions, G to I colour moissanite reads as very close to colourless.
J Colour and Below
A visible warmth or faint yellow or grey cast becomes apparent. This is more noticeable in larger stones and under neutral or cool lighting.
Bellari sources D colour moissanite across its jewellery range. In a piece such as a tennis bracelet where multiple stones sit in a continuous line, colour consistency across all stones is as important as the grade of any individual stone. Mismatched colour grades result in a line that reads as uneven.
How Moissanite Compares to Diamond
Moissanite and diamond are distinct gemstones. They have different chemical compositions, different crystal structures, different optical properties, and different origins. Understanding the actual differences is more useful than positioning one stone against the other.
Optical Character
Diamond is known for its brilliance, the intensity of white light returned through the crown of the stone. Moissanite has a higher refractive index and stronger dispersion, producing more coloured fire alongside its white brilliance. Under direct sunlight or a spotlight, this difference is most visible.
Under diffused indoor lighting or overcast daylight, the two stones can appear visually similar to an observer who has not studied gemstones closely.
Hardness
Diamond is harder than moissanite at 10 versus 9.25 on the Mohs scale. In practical terms, both stones are highly resistant to scratching under the conditions of everyday wear. The difference has no meaningful effect on how either stone holds up in a normal setting.
Composition
Diamond is composed of carbon atoms arranged in a cubic crystal structure. Moissanite is composed of silicon carbide with a hexagonal crystal structure. They are chemically distinct materials.
Distinguishing the Two
A trained gemologist can distinguish moissanite from diamond using testing equipment. Standard diamond testers that measure thermal conductivity alone may give an inconclusive reading for moissanite, as moissanite has similar thermal conductivity to diamond. A tester that measures both thermal and electrical conductivity will distinguish the two correctly.
To the naked eye, distinguishing moissanite from diamond requires close comparison under controlled conditions. In normal wear, the two are not reliably distinguishable without instruments.
What Moissanite Looks Like Over Time
Moissanite does not cloud, fade, or change colour with age. The silicon carbide crystal is chemically stable and does not react with moisture, skin oils, or common household products in a way that permanently affects the stone's appearance.
A build-up of product near the setting can reduce the amount of light passing through the pavilion of the stone, making it appear temporarily less bright. This resolves with cleaning.
How to Care for Moissanite Jewellery
Regular cleaning with warm water, a small amount of mild dish soap, and a soft-bristled brush is sufficient maintenance. Allow the piece to soak briefly, brush gently through the setting, rinse under clean running water, and pat dry with a soft cloth.
For pieces with rhodium-plated settings, avoid ultrasonic cleaners, harsh chemical solutions, and abrasive polishing cloths. These can wear the plating rather than the stone, but the stone itself is unaffected.
The Sparkle Guide at Bellari covers stone care and metal maintenance in detail across all product types in the range.
Moissanite Jewellery: What Is Available
Moissanite is used across a wide range of jewellery types. It is well suited to any setting where a hard, optically consistent, and durable stone is required.
Bellari's range includes moissanite tennis bracelets in 2mm and 3mm stone sizes, tennis necklaces, stud earrings in oval, round, pear, radiant, and emerald cut, eternity bands, and eternity rings. All pieces are set in rhodium-plated sterling silver, with the eternity band also available in 10K solid gold.
The moissanite tennis bracelet is where most people begin exploring the Bellari range. The moissanite earrings spans five stone cuts, each producing a different silhouette and light return. The moissanite necklaces collection includes tennis-style pieces designed to wear at the neckline with the same continuous-stone construction as the bracelet range.
The full Bellari collection covers the complete range across all product categories.
Final Thoughts
Moissanite is a silicon carbide gemstone grown in laboratory conditions and first identified in meteorite material in 1893. It has a Mohs hardness of 9.25, a refractive index higher than diamond, and a dispersion rate more than twice that of diamond, producing strong fire and white brilliance together.
It does not cloud or degrade over time. It is graded for colour on the same scale as diamond, with D colour indicating a colourless stone. It is a distinct material from diamond, not a substitute for it, with its own optical character and properties.
Understanding what moissanite is makes it easier to evaluate a piece before purchase, compare options accurately, and care for the stone correctly over time.
