Zircon

Zircon is a natural precious gemstone known for its exceptional brilliance, fire, and wide array of colours, including blue, yellow, brown, green, and rare red hues. It is one of the oldest minerals on Earth, dating back over 4.4 billion years. Often confused with cubic zirconia, zircon is a completely natural gemstone prized for its diamond-like lustre. It is also notable for its strong double refraction, which gives it a distinctive sparkle.

Chemical Composition: Zirconium Silicate (ZrSiO₄)

Crystal System: Tetragonal

Refractive Index: 1.78 to 1.99

Specific Gravity: 3.9 to 4.8

Double Refraction: 0.001 to 0.059

Mohs Hardness: 6.5 - 7.5

Lustre: Adamantine to Vitreous

Zircon is found in several gem-producing regions worldwide. The most important sources include Cambodia, Sri Lanka, Myanmar (Burma), Vietnam, Madagascar, Tanzania, and Australia. Cambodia primarily produces highly prized kingfisher blue zircons, while Sri Lanka yields beautiful golden, brown, and colourless varieties. Australia contains some of the oldest zircon deposits, dating back billions of years.

Yes, zircon can be used in engagement rings, but with some caution. With a Mohs hardness of 6.6 to 7.5, it is softer than sapphires and diamonds, making it more prone to scratches and abrasions over time. However, its exceptional brilliance and affordability make it a stunning alternative to diamonds. To enhance the zircon's durability over time, a protective setting such as a bezel set or diamond halo are recommended.

A zircon's value is determined by colour, clarity, size, and origin. The most valuable zircons display intense blue, golden, or rare imperial red hues. Clarity is also essential; zircons with high transparency and minimal inclusions are more valuable. Larger carat sizes are rarer and command higher prices, especially for fine-quality specimens. Cambodian blue zircon and Sri Lankan golden zircon are among the most sought-after varieties.

Zircon is often heat-treated to enhance its colour and clarity. The most common treatment involves heating brown zircon to produce vibrant blue, golden, or colourless varieties. This process removes undesired overtones and enhances the gem's brilliance. Heat treatment is permanent and widely accepted in the gemstone trade. Some natural zircons remain untreated, especially those with desirable colours like rare imperial red.

The rarest zircon is Imperial Red Zircon, a highly coveted variety displaying deep red-orange hues with an intense fire that rivals fine spinel or ruby. This rare zircon is found in Cambodia, Sri Lanka, and Madagascar, and its finest specimens showcase strong saturation and brilliance. Due to its rarity, Imperial Red Zircon is one of the most valuable zircon types, often collected by connoisseurs and used in high-end jewellery.

Zircon is the traditional birthstone for December, alongside turquoise and tanzanite. Historically, blue zircon has been the most popular December birthstone choice due to its icy, wintry hues.

Zircon has been revered throughout history for its spiritual and metaphysical properties. It is believed to symbolize wisdom, grounding, and protection. In ancient times, zircon was thought to bring prosperity, improve sleep, and ward off evil spirits. Blue zircon is associated with calmness and communication, while golden zircon represents wealth and energy. Throughout history, royalty and nobility wore zircon as a talisman for good fortune.

Natural zircon often contains minor inclusions and exhibits strong double refraction, making it appear slightly "blurred" when viewed under magnification. Synthetic zircons don't exist; imitations such as cubic zirconia (CZ) and synthetic spinel are sometimes misrepresented as zircon. To ensure authenticity, purchasing from a reputable jeweller or gemstone dealer is best.