Opal displays such a plethora of forms and colours that each and every one of these gemstones is unique in its own way. Opal is a hugely popular gemstone thanks to its play of colour that changes depending on the angle at which the stone is viewed (opalescence). Indeed, the finest Opals can be more valuable than Diamond.
An Opal’s value is determined by many factors including the intensity and distribution of its opalescence, the saturation of body colour, the play of colour and the transparency.
Sources: The Opal is the national gemstone of Australia, with other key sources being Ethiopia, Sudan, Hungary, Honduras, Brazil, Mexico and the USA.
Similar gemstones: The unique and distinctive colour play of the Opal means it is rarely, if ever, mistaken for any other gemstone.
Colour palette: White, colourless, yellow, red, blue, green, grey, brown, black, with the most common play of colour being yellow, blue and green, and the rarest violet, red and orange. Opalescence is usually milky blue in colour but can occur in other colours.
White is the most common of the Opal body colours, while Black is considered the most valuable. Green and Blue Opals, which usually display spots of red, are very rare.
Fire Opal comes in variations of yellow, orange or red.
More information about the Opal: Opal is the Birthstone of October, the 14th Wedding Anniversary gemstone and associated with the qualities of wisdom, purity and hope.
Similar gemstones: The unique and distinctive colour play of the Opal means it is rarely, if ever, mistaken for any other gemstone. However, Fire Opal can resemble Topaz, Citrine and Carnelian, with red Fire Opals resembling Ruby.