Google Links

Follow the links below to find material targeted to the unit's elements, performance criteria, required skills and knowledge

Elements and Performance Criteria

  1. Select the machinery and consumables for production cutting opal.
  2. Identify sources of rough opal and consumables and obtain supplies.
  3. Review the layout of the workshop and set up machinery and equipment for production cutting.
  4. Cut and polish opal to industry requirements within the time constraints of the production process.

Evidence Required

The evidence guide provides advice on assessment and must be read in conjunction with the performance criteria required skills and knowledge range statement and the Assessment Guidelines for the Training Package

Critical aspects for assessment and evidence required to demonstrate competency in this unit

To achieve competency in this unit a person must be able to cut opal in a production environment meeting standards of quality and working with commercial constraints

The assessment must confirm the ability to select machinery and consumables to organise the workshop for production cutting and cut opals to industry standards within commercial constraints All OHS issues must be handled appropriately

Competence in this unit must be assessed over a period of time in order to ensure consistency of performance over the range of variables and contexts applicable to the work environment

Context of and specific resources for assessment

This unit may be assessed in a work environment in a simulated work environment or in a combination of these situations

Method of assessment

For valid and reliable assessment of this unit evidence should be gathered through a range of methods to indicate consistent performance

Assessment of this unit of competence will usually include observation of processes and procedures oral andor written questioning on underpinning knowledge and skills and other methods as required

Assessment methods should closely reflect workplace demands eg literacy and the needs of particular groups eg people with disabilities and people who may have literacy or numeracy difficulties such as speakers of languages other than English remote communities and those with interrupted schooling

Assessment of this competency requires access to

production cutting and polishing equipment tools and consumables

a qualified workplace assessor or assessment team


Range Statement

The range statement relates to the unit of competency as a whole. It allows for different work environments and situations that may affect performance. Bold italicised wording, if used in the performance criteria, is detailed below. Essential operating conditions that may be present with training and assessment (depending on the work situation needs of the candidate, accessibility of the item, and local industry and regional contexts) may also be included.

Machinery may include:

cabochon cutting machine

cabochon pre-former

diamond sintered wheel grinder

faceting unit pre-former

high speed sanding unit

multi bade trim saw

pumice pre-polishing unit

soft diamond wheel sanding and polishing unit

spongy wheel sanding unit

triplet slicing machine

UV light box

vibro tumbler.

Consumablesand adhesives may include:

#400 acid treated silicon-carbide powder

backing material

blackening agent

dopping wax or adhesive

epoxy adhesive

grinding wheels

polishing powder (cerium oxide)

polishing wheels (diamond or felt)

red sealing wax

rough opal

sanding wheels (diamond or spongy)

trim saw blades

triplet slicing blades, 120, 140, 160,180.

triplet tops

UV adhesive

water and electricity.

Backing materials may include:

black jade

black potch (best)

boulder iron stone

clear or transparent potch

dark grey potch

glass (triplet only)

obsidian (black)

vitrolite (triplet only).

Stock management system may include:

avoiding cutting irregular sizes or shapes to minimise slow stock

maintenance of rough opal and consumables supplies

regular checks with suppliers for continuity of consumables

stock popular sizes to meet new markets.

Dopping techniques may include:

5-minute epoxy glue

aluminium or wooden dop-sticks

collapsible rack for holding dop-sticks

green or red sealing wax

vacuum dopping

wood glues.

Standard millimetre sizes may require:

consistent accurate sizes

no grinding marks or sanding marks on surface

very high polish required

when shaping, keep the setting into jewellery in mind.