The Value of Australian Opal

The Value of Australian Opal

There is no denying that Australian opal is considered one of the world’s most valuable gemstones. Opal is said to be a diminishing resource, and even though mining continues today, the production has dropped to an all-time low compared to its hey-day of the 1980’s Opal Rush.

Due to its scarcity, it is rumoured that Australian opal is set to increase in value anywhere up to 25% per year in its rarer forms, and up to 15% per year in its more common forms. 

How is opal valued?

Compared to other valuable stones such as diamonds, rubies and sapphires, opals are far more complex to value. They have a large range of valuation characteristics which need to be taken into consideration, specifically the following:

Opal type/body tone - The difference between the value of a jet black body tone compared to grey can be miniscule in colour (just one point on the Body Tone chart), but much larger in value. The darker the better. Opal types include black opal, grey/dark opal, white/light opal and boulder opal.

Play of colour - The colours exhibited within the opal are known as ‘play of colour’. Some colours and colour combinations are valued higher, for example opals that have mixed colours of red, blue and green are the most valuable. The 'dominant colour' in an opal can also affect its value.

Brightness - Referred to as ‘the fire’. The brighter and more iridescent result in a higher value. 

Size and weight - Like all precious gemstones, an opal weight is depicted in carats, and measured in millimeters.

Shape – Value can be added depending on whether the opal is flat on top or is domed. Domed surfaces can vividly display play of colour better, and are more desired for certain jewellery settings.

Cut & polish - An irregular free-form opal is valued differently to an opal that has been lovingly cut.

Faults - Scratches, cracks or marks that are noticeable in the face of the stone will have a dramatic effect on the value.

Solid & natural - Authentic solid opals are valued far more highly than doublets or triplets.  

Jewellery setting - The addition of gold (and its quality), as well as additional gemstones increases the overall value of your opal jewellery.

Which are the rarest and most valuable types of Australian opal?

Black Opal: Lack of supply of black opal is driving demand owing to its rarity and beauty. Black opal is the most prized opal, and is valued anywhere from AU$1,000 per carat up to AU$15,000 per carat (and beyond!). Black opal is considered one of the most valued gemstones on the planet, and is much rarer than diamond! 

Boulder Opal: It is predicted that boulder opal is going to run out in the next 5-10 years because of the difficulty clearing Native Title and EPA requirements. In addition, boulder opal only makes up for just 2% of all opal mined in Australia, and is found only in scattered deposits in a small area of Queensland. It is in very rare supply, and therefore an extremely valuable commodity. Good quality boulder opal is valued at around $3,500 per carat.

Personal valuation

‘Value’ can be down to individual interpretation. At the end of the day, the most valuable thing is that YOU personally love your opal. Beauty is in the eye of the beholder, and you’ll find when choosing your opal, you won’t choose it - it will choose you. 

If you are interested in getting your opal valued, you’ll need to contact an independent opal valuer. Having a signed Certificate of Authenticity will help. 

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