With each Opal it is important to consider the following –
- Colours present in the stone which is also called ‘play of colour’
- Brightness of the stone also referred to as the ‘fire’
- Whether the stone is black, dark, boulder or light body tone
- The care of Opals and Opal jewellery
- How saturated or intense the colours are
- Whether the stone appears dull from any angles
- Whether the stone is flat on top or has a rounded dome
- The size and weight of the stone
- The cut of the stone – even oval or irregular free-form
- The value of the setting the Opal is in, if set – the gold, accent diamonds and workmanship
Opals that have mixed spectral colours of red, blue, green are the most valuable, often fetching many thousands of dollars per carat, particularly if they are bright.
However, there are many stones in blue and green that can range down to as low as $20 per carat retail. Brightness and fire is major consideration, driving up the value if the stone is very bright.
Doublets are typically one tenth the value of the solid equivalent, with triplets being even cheaper.
If looking at stones and Opal jewellery pieces in various outlets it is important to compare “like with like” – to consider whether particular stones have the same brightness, same play or colour or quality of setting and whether other considerations such as the showroom lighting are the same, when checking prices.