How to Measure Australian Opal Quality

How to Measure Australian Opal Quality

Opals are a true treasure, cauptivating onlookers with their mesmerising beauty, intricate array of colors, and effervescent quality. As a diverse gemstone, valuing them can be a challenging task for industry experts. Opals are a gemstone unlike any other, making them the perfect centrepiece to a jewellery collection: either the staple stone in a necklace, pair of earrings, or an engagement ring. 

An opal will be the ideal addition to your jewellery collection. This blog will help uncover how to measure Australian opal quality so that you have a better understanding of the value process. 

Where are Opals Found in Australia? 

Australia is widely regarded as the home of opals due to how many are produced here. 

Four opal towns have made a household name for themselves in Australia. They are Coober Pedy, Lightning Ride, White Cliffs, and Andamooka. These towns are famed in parallel for their beautiful opals and harsh living conditions. With wild landscapes and a hot climate, these four towns produce the majority of Australia’s opals, and each town specialises in a different variety of opals. 

Coober Pedy in South Australia is the world’s main producer of white opal. 

Lightning Ridge in New South Wales produces beautiful black opals, which is the most sought-after opal in the world. 

White Cliffs in northwestern New South Wales produces white and crystal opals. 

Andamooka in South Australia also produces white and crystal opals. 

Are there Different Grades of Opals?

In short - yes, there are. Opals are measured according to their colour and body tone, with 9 subcategories working out the overall value of an opal. The categories range from N1 to N9, with N1 representing the darkest type of opal, and N9 being the lightest shade.


What are the Most Valuable Types of Opals? 

The coloration of an opal holds immense significance in determining its overall worth and value in the gemstone industry.

The dominant colour of opal will be the main indicator of the price - red is the rarest colour and the most valuable. The colour value follows a rainbow pattern: red first, then orange, yellow, green, and blue. 

The brightness of the opal will also be a high indicator of its value. Opals have three brightness ratings: Subdued, Bright, and Brilliant. Brilliant is the most sought-after brightness and is the most expensive. However, no matter what the brightness of your opal is - it’ll still be beautiful!

Opals also have different pattern types or arrangements of colours throughout the stone. The most common pattern is floral as it covers a wide range of pattern types, with no set order or variance. Most opals come with this pattern. The most valuable types of pattern include Rolling Flash, which features a backdrop of mostly one colour with a bright flash that rolls around the stone, Pinfire, which features small dots of colour that resemble stars in the night sky, and Broad Flash, which are large sections of colour that flash brightly in the light. 

Finally, you may have seen that opal can also have different A-grade categories. These categories go from A, meaning “Good” and includes the top 75% of opal stones, followed by  AA meaning “Better”, which includes the top 33% of opal stones. Then AAA, which means “Best” and includes the top 10% of opal stones, before AAAA, or “Heirloom” which is where the top 1% of opals sit. 

How are Opals Cut? 

Opals have a cutting style that considers their colour, pattern, and clarity. Opal cutters will shape the opal in a way that brings out the stone’s best features and displays of colour, while still trying to retain its size. The cut of an opal might be more unusual than a traditional gemstone, but the result will be symmetrical. 

Opals are a unique and beautiful gem and we are so lucky that Australia is home to so many beautiful stones. An opal jewellery piece will certainly be unique and promises to be an eye-catching addition to an already existing collection, or the perfect first piece. 


Jason Ree takes pride in its ready-to-wear opals and has plenty of options to choose from. Choose an opal jewellery piece for yourself today, or design your perfect piece by booking a conversation with Jason Ree today.