How to Tell if an Opal is Real
Australian opals are among the world’s most captivating gemstones, celebrated for their spectacular play of colour and natural beauty. If you’re looking for a trusted Opal Shop Sydney visitors and locals rely on, knowing how to identify a genuine Australian opal is essential. Unfortunately, not every opal offered for sale is a solid natural opal. Many buyers are unaware that some stones are assembled, treated or even manufactured to imitate genuine opals.
Whether you’re purchasing your first opal or adding to a collection, understanding how to identify a real opal will help you buy with confidence.
What Is a Real Opal?
A real opal is a naturally formed gemstone created over millions of years as silica-rich water slowly deposits microscopic silica spheres within cracks and cavities in rock. These spheres diffract light, producing the vibrant flashes of colour known as play of colour.
Australia produces around 90–95% of the world’s precious opals, making Australian opals the benchmark for quality, rarity and durability.
Types of Opals You May Encounter
1. Solid Natural Opal
A solid opal is cut from a single piece of natural opal and is considered the most valuable and durable type.
Solid opals include:
- Black Opal
- Boulder Opal
- White Opal
- Crystal Opal
These are the finest choice for jewellery and collectors because the entire stone is naturally formed.
2. Doublet Opal
A doublet consists of a thin slice of genuine opal permanently bonded to a dark backing material.
While the opal layer is natural, the stone is assembled to enhance its appearance and reduce cost.
How to identify a doublet
- A visible straight joining line can often be seen from the side.
- The backing is usually dark ironstone, potch or another material.
- The opal layer is very thin.
Doublets can be beautiful but are generally less valuable than solid opals.
3. Triplet Opal
A triplet is made from three layers:
- A thin slice of natural opal
- A dark backing
- A clear protective cap, usually quartz or glass
Triplets often display very bright colours but can appear almost too perfect.
How to identify a triplet
- A clear dome sits over the opal.
- Side views reveal three distinct layers.
- The colour pattern appears magnified beneath the clear cap.
Triplets are popular for affordable jewellery but are not considered solid opals.
4. Synthetic Opals
Synthetic opals are created in laboratories and have the same basic chemical composition as natural opals but are manufactured in weeks rather than formed over millions of years.
Signs of a synthetic opal
- Highly uniform colour.
- Repeating patterns resembling a mosaic, snake skin or chicken wire.
- Very consistent brightness across the entire stone.
- Little natural variation.
Although attractive, synthetic opals have significantly lower rarity and value than natural Australian opals.
5. Imitation Opals
Imitation opals are made from materials such as glass, plastic or resin and simply imitate the appearance of an opal.
Unlike synthetic opals, they are not composed of natural silica.
Six Ways to Tell if an Opal Is Real
1. Look for Natural Colour Variation
Every natural opal is unique.
The colours should move and change as the stone is viewed from different angles. Genuine Australian opals display natural variation rather than perfectly repeated patterns.
2. Examine the Side of the Stone
Viewing the edge of an opal often reveals whether it is solid, a doublet or a triplet.
A solid opal has continuous natural material throughout, while assembled stones usually show distinct layers.
3. Check the Pattern
Natural opals produce irregular, unpredictable patterns.
If the pattern repeats in a highly organised or geometric way, the stone may be synthetic.
4. Ask About Its Origin
A reputable jeweller should be able to tell you where the opal was mined.
Australian opals come from famous mining regions including:
- Lightning Ridge (Black Opal)
- Coober Pedy (White Opal)
- Winton (Boulder Opal)
- Koroit (Boulder Opal)
- Yowah (Boulder Opal)
5. Buy from a Trusted Opal Specialist
The safest way to ensure you’re purchasing a genuine opal is to buy from an experienced jeweller who specialises in Australian opals.
Ask whether the stone is:
- Solid natural opal
- Doublet
- Triplet
- Synthetic
A reputable seller will always disclose this information.
6. Request Documentation
For valuable opals, ask for:
- A valuation certificate.
- Details of the stone’s origin.
- Confirmation that it is a natural Australian opal.
Documentation provides additional confidence and can be valuable for insurance purposes.
Australian Opal vs Ethiopian Opal
Many buyers also compare Australian and Ethiopian opals.
Australian solid opals are generally regarded as more stable because they are non-hydrophane, meaning they do not absorb water. Ethiopian hydrophane opals can temporarily change appearance when they absorb moisture or oils, which may affect their colour until they dry out.
Both can be beautiful gemstones, but Australian opals are especially prized for their long-term stability, making them an excellent choice for everyday jewellery.
Frequently Asked Questions
Can a real opal scratch?
Yes. Opals are softer than diamonds or sapphires, so they should be treated with care. A protective setting and sensible wear will help preserve their beauty.
Are all colourful opals real?
No. Some colourful stones are synthetic or imitation opals. Examining the structure and purchasing from a reputable jeweller are the best ways to ensure authenticity.
Are doublets and triplets fake?
No. They contain genuine opal, but they are assembled stones rather than solid natural opals. Reputable jewellers will clearly disclose this.
Is every Australian opal a solid opal?
No. Australian opals may be sold as solid opals, doublets or triplets. A reputable jeweller will clearly disclose which type you are purchasing.
Why are Australian opals more valuable?
Their rarity, natural beauty, durability and limited supply make Australian opals some of the world’s most sought-after gemstones.
Can Australian opals be worn every day?
Yes. Solid Australian opals are suitable for everyday wear when set correctly and treated with reasonable care.
How We Authenticate Every Australian Opal
Every opal at Cosmopolitan Jewellers is carefully inspected by experienced opal specialists. We verify whether each stone is a solid natural opal, doublet or triplet before it is offered for sale. Our team also identifies the opal type, mining region and overall quality, ensuring complete transparency for every customer.
Buy Genuine Australian Opals with ConfideBuy Genuine Australian Opals from Sydney’s Opal Specialistsnce
Visit Cosmopolitan Jewellers in The Rocks, Sydney to discover one of Australia’s largest collections of solid Australian opals. From rare Lightning Ridge black opals to spectacular Queensland boulder opals, every gemstone is carefully selected for its natural beauty and authenticity. Whether you’re shopping in-store or online, our experienced team is here to help you choose an opal you’ll treasure for generations.
With decades of experience specialising in Australian opals, our team has helped thousands of customers from around the world select genuine opal jewellery with confidence.
Expert Tip
If a deal seems too good to be true, it usually is. Genuine solid Australian black opals are among the rarest gemstones in the world. Extremely low prices often indicate a doublet, triplet or synthetic stone rather than a solid natural opal.
