"Nature's Fireworks" - A Beginner's Guide to OPAL - Parts 6 and 7: Valuing Opals and Opal Dictionary

Valuing Opals

When determining the value of an opal, several factors are involved:

  • Type of opal

  • Soundness

  • Base colour

  • Fire colour

  • Colour pattern

  • Brightness of fire

    • Background (base) Colour:

    Solid precious opal is more valuable than a doublet or triplet, and black opal is more valuable than boulder opal, and so forth. The darker the body colour, the more valuable the gem.

    Fire Colour:

    The clarity of the opals colour is critical when determining the value of the opal. Opal is graded according to its colour, with red fire being the most rare, followed by green/orange, green/blue, blue, and finally, purple. However, brilliance and clarity of colour, along with proportional pattern are the main decision makers; a brilliant blue/green opal can cost more than a dull red. An opal displaying a bright