About Hydrophane Opal

Hydrophane or Matrix Opal

Cloudy white opal from Andamooka, South Australia, should be mentioned here. This is a porous, or hydrophane, opal. We'll talk about hydrophane opal a little later on when we discuss enhancing the colours of opal.

Hydrophane opal is a type of opal that is unusually porous. It does not display colours until it is immersed in water or some other liquid. When the water evaporates the colours disappear again.

Because hydrophane opals are porous it is possible to dye them to enhance the play of colour and make them appear like black opal. The dying process works by filling the pores with carbon.

This results in the excess of scattered white light being absorbed by the carbon and in turn results in colours resembling good quality black opal.

This procedure has been used with hydrophane matrix opal from Andamooka in South Australia, which contains kaolinite clay. This clay scatters white light and diminishes play of colour.

Andamooka