Elements and Performance Criteria
- Select opal for cutting as an opal doublet or triplet
- Select suitable materials for cutting as a doublet or triplet based on market requirements and characteristics of the stone
- Determine best play of colour and mark that side
- Check for flaws with powerful light source and correct if necessary
- Follow general OHS principles and safe operating procedures when using machinery for opal cutting
- Flatten opal and base
- Cement components together
- Blacken flattened surface with appropriate blacking agent
- Mix adhesive in line with manufacturers’ instructions
- Ensure stone is cemented with the best colour face down
- Cement flattened surfaces together eliminating excess adhesive and air bubbles
- Allow adhesive to harden following manufacturers’ instructions
- Pre-form opal doublet
- Convert doublet to triplet
- Manufacture a triplet working with a very thin opal layer
- Lap the colour surface of the opal until a thin layer of opal remains on the backing
- Clean and dry stone
- Cement manufactured triplet top or preferred alternative to the opal surface, eliminating excess adhesive and air bubbles
- After curing, grind the stone to expose both joins