When shopping for engagement rings or fine jewellery, one of the most important decisions you’ll face is choosing between moissanite vs diamond. Both gemstones offer stunning brilliance and durability, but they differ significantly in their origins, properties, appearance, and price points. This comprehensive guide will help you understand these differences and make an informed decision that suits your preferences and budget.
What Are Diamonds?
Diamonds are naturally occurring gemstones formed deep within the Earth’s mantle under extreme pressure and temperature over billions of years. Composed of pure carbon atoms arranged in a crystalline structure, diamonds have been treasured throughout human history as symbols of love, commitment, and luxury. Today, diamonds are available in both natural and lab-grown varieties, with lab-grown diamonds possessing identical chemical, physical, and optical characteristics to their mined counterparts.
What Is Moissanite?
Moissanite is a gemstone composed of silicon carbide that was first discovered in 1893 by French scientist Henri Moissan in a meteor crater in Arizona. While naturally occurring moissanite is extremely rare, all moissanite used in jewellery today is lab-created. This gemstone has gained tremendous popularity as an alternative to diamonds, particularly for engagement rings, due to its remarkable brilliance and affordability.
Key Differences Between Moissanite and Diamond
1. Chemical Composition and Structure
The fundamental difference between these two gemstones lies in their chemical makeup. Diamonds consist entirely of carbon atoms bonded in a cubic crystal structure, while moissanite is made of silicon carbide with a different crystalline arrangement. This distinction affects how each stone interacts with light and contributes to their unique visual characteristics.
2. Brilliance and Fire
One of the most noticeable differences is how these stones handle light. Brilliance refers to the white light reflected from a gemstone, while fire describes the dispersion of light into rainbow colours. Moissanite has a higher refractive index than diamond, resulting in more brilliance and significantly more fire. This means moissanite displays more colourful flashes of light, creating what many describe as a rainbow-hued sparkle. Diamonds, on the other hand, exhibit a more subtle, classic white sparkle that many people associate with traditional elegance.
3. Hardness and Durability
Both gemstones are exceptionally durable, making them suitable for daily wear. Diamonds rank 10 on the Mohs hardness scale, making them the hardest naturally occurring substance on Earth. Moissanite follows closely behind at 9.25, which still represents outstanding hardness and resistance to scratching. For practical purposes, both stones are tough enough to withstand the rigours of everyday life, making them equally suitable for engagement rings and other frequently worn jewellery.
4. Colour
When examining colour, diamonds are graded on a scale from D (colourless) to Z (light yellow or brown). The most valuable diamonds are those in the colourless to near-colourless range. Moissanite, particularly in larger sizes, can sometimes display a slight yellow or greyish tint in certain lighting conditions. However, modern moissanite production has improved significantly, with many high-quality moissanites appearing colourless to the naked eye. Under certain lighting, moissanite may show more colourful reflections due to its higher dispersion rate.
5. Price Point
Perhaps the most compelling difference for many shoppers is the price. Moissanite typically costs a fraction of what a comparable diamond would cost—often 10% or less of a diamond’s price. This dramatic price difference allows buyers to purchase a much larger stone for the same budget or allocate more funds toward the setting, wedding expenses, or other priorities. In Australia, moissanite engagement rings can range from under $400 to around $5,000, while diamond rings of similar size and quality could cost several times more.
6. Ethical and Environmental Considerations
Both moissanite and lab-grown diamonds offer ethical advantages over mined diamonds. Since moissanite is exclusively lab-created, it carries no concerns about mining practices or conflict stones. The production of moissanite has minimal environmental impact compared to diamond mining. Lab-grown diamonds share these ethical benefits, offering the same physical properties as natural diamonds without the environmental toll of mining operations.
7. Value Retention
Diamonds, particularly natural ones, have historically held their value better than moissanite. Natural diamonds can be considered an investment and may retain resale value over time, though they rarely appreciate significantly. Moissanite, being lab-created and more affordable, has minimal resale value. However, for many people purchasing engagement rings, the sentimental value far outweighs any potential resale considerations.
How to Identify the Difference
To the untrained eye, moissanite and diamonds can look remarkably similar. However, several characteristics can help differentiate them. Moissanite’s double refraction property means that when viewed under magnification, you may notice a doubling effect in the stone’s facets. Additionally, moissanite’s higher dispersion creates more colourful light reflections, which can be particularly noticeable in bright lighting or sunlight. Professional jewellers can use specialised testing equipment to definitively identify each stone, as moissanite’s high thermal conductivity can sometimes register as a diamond on basic diamond testers.
Which Should You Choose?
The choice between moissanite and diamond ultimately depends on your personal preferences, values, and budget. Choose a diamond if you value traditional symbolism, prefer the classic white sparkle, want a stone with potential resale value, or simply love the heritage and prestige associated with diamonds. Consider moissanite if you’re working with a limited budget but want a large, brilliant stone, appreciate the unique rainbow-coloured fire, prioritise ethical sourcing and environmental responsibility, or prefer to allocate your budget toward other aspects of your life together.
December 2025 Offers on Moissanite and Diamonds in Australia
For Australian shoppers looking to purchase moissanite or diamond jewellery in December 2025, there are several exciting opportunities to secure excellent deals:
Black Friday Sales (Late November – Early December)
Many Australian jewellers extended their Black Friday sales into early December. Major retailers like Michael Hill offered Black Friday jewellery deals on gold, silver, and diamond pieces, with the sale period running until early December. Moi Moi Fine Jewellery featured exclusive Black Friday pricing on both lab-grown diamonds and their premium SUPERNOVA Moissanite collections, offering customers the chance to purchase engagement rings, wedding bands, and fine jewellery at reduced prices.
Pre-Christmas Shopping Events
Several Australian jewellers are launching special events throughout December. TMC Fine Jewellers announced the opening of their new flagship showroom in mid-December with special promotional activities. This presents an excellent opportunity for shoppers to explore both moissanite and diamond options with potentially exclusive opening offers.
For those seeking premium moissanite and lab-grown diamond jewellery, Moi Moi Fine Jewellery (https://www.moimoi.com.au/) offers exquisite collections featuring their renowned SUPERNOVA Moissanite line. With flagship stores in Sydney and Melbourne, Moi Moi provides expert guidance and exceptional craftsmanship, making them an ideal destination for December jewellery shopping.
Boxing Day Sales (December 26 onwards)
Boxing Day represents one of Australia’s biggest shopping events, and jewellery retailers traditionally offer substantial discounts. Based on current information, several major retailers are planning significant Boxing Day sales:
SH Jewellery started their Boxing Day sale early on December 18, 2024, running until January 20, 2025, with 10% off all diamond, gold, and gemstone jewellery
Shiels offers their annual Boxing Day jewellery sale with discounts across their extensive range of engagement rings, earrings, bracelets, and necklaces, with financing options including Afterpay and Zip
Michael Hill participates in Boxing Day sales with significant discounts on quality jewellery pieces, including engagement rings and gemstone jewellery
Grahams Jewellers features Boxing Day deals both online and in their South Australian stores
Myer runs their Boxing Day sale from December 26th through January 11th, 2026, featuring jewellery alongside other product categories
Where to Shop
Australian shoppers have numerous options for purchasing moissanite and diamond jewellery:
For Moissanite Specialists:
Diamonds Factory Australia offers an extensive online selection of moissanite engagement rings with customisation options
Austen & Blake features moissanite engagement rings ranging from under $400 to $5,000
Moi Moi Fine Jewellery carries their SUPERNOVA Moissanite collection in Sydney and Melbourne flagship stores
Moissanite Gemstones International provides custom-made moissanite and lab diamond rings with complimentary design consultations
Cullen Jewellery offers moissanite engagement rings handcrafted in their Australian workshop with ethical, sustainable practices
For Both Moissanite and Diamonds:
Diamondrensu AU specialises in both lab-grown diamonds and moissanite, shipping throughout Australia and New Zealand
Most major chain jewellers now carry both options, allowing for side-by-side comparisons
Tips for December Shopping
To maximise your savings during December 2025, consider booking appointments at showrooms to receive personalised service and potentially access exclusive offers. Many retailers now offer virtual consultations, making it convenient to explore options from home. Take advantage of financing options like Afterpay, Zip, and other buy-now-pay-later services that are commonly available. Start your research early in December to avoid the rush and ensure you have time to make a considered decision. Don’t hesitate to compare prices across multiple retailers, as December sales can vary significantly between stores.
Conclusion
Both moissanite and diamonds offer stunning beauty and exceptional durability for engagement rings and fine jewellery. Moissanite provides an affordable, ethical alternative with brilliant sparkle and rainbow fire, while diamonds offer timeless tradition and classic elegance. December 2025 presents excellent opportunities for Australian shoppers to purchase either gemstone at competitive prices, particularly during Boxing Day sales that extend into January. Whether you choose moissanite for its value and unique brilliance or diamond for its heritage and prestige, you’ll be selecting a gemstone that symbolises your commitment and can be treasured for a lifetime.
The most important consideration isn’t which stone is objectively “better,” but rather which one resonates with your personal values, aesthetic preferences, and budget. Both are beautiful choices that will create lasting memories.
