CSIRO and a consortium of Australian Opal miners (Opal Producers
Australia Limited) have unveiled the world's first automated
device to grade opals using image analysis, at the 2009 National
Council of Jewellery Valuers forum in Sydney. CSIRO Mathematical
and Information Sciences image analyst Leanne Bischof helped
develop the Gemmological Digital Analyser (GDA). Ms Bischof said
that opals have a unique range of colour characteristics that
makes them by far the most difficult gemstone to appraise.
'Qualities such as 'flash,' the way an opal reflects light and
colour as it is rotated, can vary with human eyesight and
lighting conditions,' Ms Bischof said. 'A person's judgement of
an opal's colours, the brightness of those colours and the area
each of them covers is a really difficult task, even for a
skilled opal assessor. You really need objective image analysis
and automation to assist with that.' Incorporating the expert
knowledge of over 60 opal industry professionals, CSIRO designed
a GDA prototype with A