A .pdf version of the Powerpoint Presentation shown at the Symposium is available at:
http://www.opalhorizon.com/Portals/0/Opalppt-GIASymp5-28final%20(2).pdf
OR download the Brochure Version at: http://www.opalhorizon.com/Portals/0/BROCHURE(05.18.11).pdf
The new Opal Horizon grading system only applies to natural precious opal and is based on the evaluation of three quantifiable grading criteria.
The three quantifiable Cs
The three quantifiable criteria defined by Opal Horizon are Category, Colour and Cut.
“Category” This describes the opal as one of three types each defined by the presence and degree of host rock in the opal.
“Colour” The criteria applied to colour assigns points according to the opal face, body tone, play of colour, brightness, pattern, directionality and special attributes.
“Cut” The quality of the cut is determined by the opal’s finish & polish, ease of setting, symmetry or balance and exclusion of defects.
Each of the 3 Cs is graded individually on a 100 points maximum scale. The three scores are then added and result in a final comprehensive quality score. This final score provides the accurate, comprehensive and credible grading of each opal and enables the opal to then be valued at current market prices for that grade.
The wholesale pricing structure will be guided by the new quality grading system. OHZ will make available for purchase internationally not only the precious opal from its own mines, but also will seek to centralize the distribution of opals through cooperative partnership arrangements and by purchasing from other opal suppliers. It is estimated that 95% of precious opal is produced in Australia, and OHZ expects it (along with its partner producers and suppliers) will account for a significant percentage of global sales of this gemstone.
